diff --git a/docs-xml/smbdotconf/printing/lppausecommand.xml b/docs-xml/smbdotconf/printing/lppausecommand.xml
index 3aa134c4377..f2518d3def0 100644
--- a/docs-xml/smbdotconf/printing/lppausecommand.xml
+++ b/docs-xml/smbdotconf/printing/lppausecommand.xml
@@ -1,6 +1,7 @@
 <samba:parameter name="lppause command"
                  context="S"
                  type="string"
+                 constant="1"
                  xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
 <description>
     <para>This parameter specifies the command to be 
diff --git a/docs-xml/smbdotconf/printing/lpqcommand.xml b/docs-xml/smbdotconf/printing/lpqcommand.xml
index f3c17f286d1..f0161f3448d 100644
--- a/docs-xml/smbdotconf/printing/lpqcommand.xml
+++ b/docs-xml/smbdotconf/printing/lpqcommand.xml
@@ -1,6 +1,7 @@
 <samba:parameter name="lpq command"
                  context="S"
                  type="string"
+                 constant="1"
                  xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
  <description>
     <para>This parameter specifies the command to be 
diff --git a/docs-xml/smbdotconf/printing/lpresumecommand.xml b/docs-xml/smbdotconf/printing/lpresumecommand.xml
index 153ba76a693..2cee574bd73 100644
--- a/docs-xml/smbdotconf/printing/lpresumecommand.xml
+++ b/docs-xml/smbdotconf/printing/lpresumecommand.xml
@@ -1,6 +1,7 @@
 <samba:parameter name="lpresume command"
                  context="S"
                  type="string"
+                 constant="1"
                  xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
 <description>
     <para>This parameter specifies the command to be 
diff --git a/docs-xml/smbdotconf/printing/lprmcommand.xml b/docs-xml/smbdotconf/printing/lprmcommand.xml
index 4b7f3dd75c3..a595c1225c0 100644
--- a/docs-xml/smbdotconf/printing/lprmcommand.xml
+++ b/docs-xml/smbdotconf/printing/lprmcommand.xml
@@ -1,6 +1,7 @@
 <samba:parameter name="lprm command"
                  context="S"
                  type="string"
+                 constant="1"
                  xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
 <description>
     <para>This parameter specifies the command to be 
diff --git a/docs-xml/smbdotconf/printing/printcommand.xml b/docs-xml/smbdotconf/printing/printcommand.xml
index c84e45f404d..42a7188cb9a 100644
--- a/docs-xml/smbdotconf/printing/printcommand.xml
+++ b/docs-xml/smbdotconf/printing/printcommand.xml
@@ -1,6 +1,7 @@
 <samba:parameter name="print command"
                  context="S"
                  type="string"
+                 constant="1"
                  xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
 <description>
     <para>After a print job has finished spooling to 
diff --git a/docs-xml/smbdotconf/printing/queuepausecommand.xml b/docs-xml/smbdotconf/printing/queuepausecommand.xml
index 5dca45657cc..600a2baa621 100644
--- a/docs-xml/smbdotconf/printing/queuepausecommand.xml
+++ b/docs-xml/smbdotconf/printing/queuepausecommand.xml
@@ -1,6 +1,7 @@
 <samba:parameter name="queuepause command"
                  context="S"
                  type="string"
+                 constant="1"
                  xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
 <description>
     <para>This parameter specifies the command to be 
diff --git a/docs-xml/smbdotconf/printing/queueresumecommand.xml b/docs-xml/smbdotconf/printing/queueresumecommand.xml
index 4a573330048..431295a804e 100644
--- a/docs-xml/smbdotconf/printing/queueresumecommand.xml
+++ b/docs-xml/smbdotconf/printing/queueresumecommand.xml
@@ -1,6 +1,7 @@
 <samba:parameter name="queueresume command"
                  context="S"
                  type="string"
+                 constant="1"
                  xmlns:samba="http://www.samba.org/samba/DTD/samba-doc">
 <description>
     <para>This parameter specifies the command to be 
diff --git a/source3/include/proto.h b/source3/include/proto.h
index ad6f3bbf9c3..dd4aba34fed 100644
--- a/source3/include/proto.h
+++ b/source3/include/proto.h
@@ -180,15 +180,16 @@ char *talloc_sub_specified(TALLOC_CTX *mem_ctx,
 			const char *domain,
 			uid_t uid,
 			gid_t gid);
+char *talloc_sub_advanced_only(TALLOC_CTX *mem_ctx,
+			  const char *servicename, const char *user,
+			  const char *connectpath, gid_t gid,
+			  const char *smb_name, const char *domain_name,
+			  const char *str);
 char *talloc_sub_advanced(TALLOC_CTX *mem_ctx,
 			  const char *servicename, const char *user,
 			  const char *connectpath, gid_t gid,
 			  const char *smb_name, const char *domain_name,
 			  const char *str);
-void standard_sub_advanced(const char *servicename, const char *user,
-			   const char *connectpath, gid_t gid,
-			   const char *smb_name, const char *domain_name,
-			   char *str, size_t len);
 
 /* The following definitions come from lib/sysquotas.c  */
 
diff --git a/source3/lib/substitute.c b/source3/lib/substitute.c
index ea227c5ab68..c1bc05b9c15 100644
--- a/source3/lib/substitute.c
+++ b/source3/lib/substitute.c
@@ -790,7 +790,7 @@ char *talloc_sub_specified(TALLOC_CTX *mem_ctx,
 /****************************************************************************
 ****************************************************************************/
 
-char *talloc_sub_advanced(TALLOC_CTX *ctx,
+char *talloc_sub_advanced_only(TALLOC_CTX *ctx,
 			const char *servicename,
 			const char *user,
 			const char *connectpath,
@@ -799,12 +799,12 @@ char *talloc_sub_advanced(TALLOC_CTX *ctx,
 			const char *domain_name,
 			const char *str)
 {
-	char *a_string, *ret_string;
+	char *a_string;
 	char *b, *p, *s;
 
 	a_string = talloc_strdup(talloc_tos(), str);
 	if (a_string == NULL) {
-		DEBUG(0, ("talloc_sub_advanced: Out of memory!\n"));
+		DEBUG(0, ("talloc_sub_advanced_only: Out of memory!\n"));
 		return NULL;
 	}
 
@@ -858,25 +858,29 @@ char *talloc_sub_advanced(TALLOC_CTX *ctx,
 		}
 	}
 
-	ret_string = talloc_sub_basic(ctx, smb_name, domain_name, a_string);
-	TALLOC_FREE(a_string);
-	return ret_string;
+	return a_string;
 }
 
-void standard_sub_advanced(const char *servicename, const char *user,
-			   const char *connectpath, gid_t gid,
-			   const char *smb_name, const char *domain_name,
-			   char *str, size_t len)
+char *talloc_sub_advanced(TALLOC_CTX *ctx,
+			const char *servicename,
+			const char *user,
+			const char *connectpath,
+			gid_t gid,
+			const char *smb_name,
+			const char *domain_name,
+			const char *str)
 {
-	char *s = talloc_sub_advanced(talloc_tos(),
-				servicename, user, connectpath,
-				gid, smb_name, domain_name, str);
+	char *a_string, *ret_string;
 
-	if (!s) {
-		return;
+	a_string = talloc_sub_advanced_only(ctx, servicename, user, connectpath,
+						  gid, smb_name, domain_name, str);
+	if (a_string == NULL) {
+		return NULL;
 	}
-	strlcpy( str, s, len );
-	TALLOC_FREE( s );
+	
+	ret_string = talloc_sub_basic(ctx, smb_name, domain_name, a_string);
+	TALLOC_FREE(a_string);
+	return ret_string;
 }
 
 /******************************************************************************
diff --git a/source3/printing/print_generic.c b/source3/printing/print_generic.c
index b6b50062caf..c58f8ddce0b 100644
--- a/source3/printing/print_generic.c
+++ b/source3/printing/print_generic.c
@@ -56,6 +56,8 @@ static int print_run_command(int snum, const char* printername, bool do_sub,
 		return -1;
 	}
 
+	DEBUG(3, ("Incoming command '%s'\n", syscmd));
+
 	while ((arg = va_arg(ap, char *))) {
 		char *value = va_arg(ap,char *);
 		syscmd = talloc_string_sub(ctx, syscmd, arg, value);
@@ -71,6 +73,11 @@ static int print_run_command(int snum, const char* printername, bool do_sub,
 		return -1;
 	}
 
+	syscmd = lp_string(ctx, syscmd);
+	if (!syscmd) {
+		return -1;
+	}
+
 	if (do_sub && snum != -1) {
 		syscmd = talloc_sub_advanced(ctx,
 				lp_servicename(talloc_tos(), snum),
@@ -118,7 +125,7 @@ static int generic_job_pause(int snum, struct printjob *pjob)
 	/* need to pause the spooled entry */
 	slprintf(jobstr, sizeof(jobstr)-1, "%d", pjob->sysjob);
 	return print_run_command(snum, lp_printername(talloc_tos(), snum), True,
-				 lp_lppause_command(talloc_tos(), snum), NULL,
+				 lp_lppause_command(snum), NULL,
 				 "%j", jobstr,
 				 NULL);
 }
@@ -133,7 +140,7 @@ static int generic_job_resume(int snum, struct printjob *pjob)
 	/* need to pause the spooled entry */
 	slprintf(jobstr, sizeof(jobstr)-1, "%d", pjob->sysjob);
 	return print_run_command(snum, lp_printername(talloc_tos(), snum), True,
-				 lp_lpresume_command(talloc_tos(), snum), NULL,
+				 lp_lpresume_command(snum), NULL,
 				 "%j", jobstr,
 				 NULL);
 }
@@ -255,7 +262,7 @@ static int generic_job_submit(int snum, struct printjob *pjob,
 
 	/* send it to the system spooler */
 	ret = print_run_command(snum, lp_printername(talloc_tos(), snum), True,
-			lp_print_command(talloc_tos(), snum), NULL,
+			lp_print_command(snum), NULL,
 			"%s", p,
 			"%J", jobname,
 			"%f", p,
@@ -308,7 +315,7 @@ static int generic_job_submit(int snum, struct printjob *pjob,
 static int generic_queue_pause(int snum)
 {
 	return print_run_command(snum, lp_printername(talloc_tos(), snum), True,
-				 lp_queuepause_command(talloc_tos(), snum), NULL, NULL);
+				 lp_queuepause_command(snum), NULL, NULL);
 }
 
 /****************************************************************************
@@ -317,7 +324,7 @@ static int generic_queue_pause(int snum)
 static int generic_queue_resume(int snum)
 {
 	return print_run_command(snum, lp_printername(talloc_tos(), snum), True,
-				 lp_queueresume_command(talloc_tos(), snum), NULL, NULL);
+				 lp_queueresume_command(snum), NULL, NULL);
 }
 
 /****************************************************************************
diff --git a/source3/printing/printing.c b/source3/printing/printing.c
index e6caaa1222f..a50567037b1 100644
--- a/source3/printing/printing.c
+++ b/source3/printing/printing.c
@@ -1717,14 +1717,14 @@ static void print_queue_update(struct messaging_context *msg_ctx,
 	/* don't strip out characters like '$' from the printername */
 
 	lpqcommand = talloc_string_sub2(ctx,
-			lp_lpq_command(talloc_tos(), snum),
+			lp_lpq_command(snum),
 			"%p",
 			lp_printername(talloc_tos(), snum),
 			false, false, false);
 	if (!lpqcommand) {
 		return;
 	}
-	lpqcommand = talloc_sub_advanced(ctx,
+	lpqcommand = talloc_sub_advanced_only(ctx,
 			lp_servicename(talloc_tos(), snum),
 			current_user_info.unix_name,
 			"",
@@ -1737,14 +1737,14 @@ static void print_queue_update(struct messaging_context *msg_ctx,
 	}
 
 	lprmcommand = talloc_string_sub2(ctx,
-			lp_lprm_command(talloc_tos(), snum),
+			lp_lprm_command(snum),
 			"%p",
 			lp_printername(talloc_tos(), snum),
 			false, false, false);
 	if (!lprmcommand) {
 		return;
 	}
-	lprmcommand = talloc_sub_advanced(ctx,
+	lprmcommand = talloc_sub_advanced_only(ctx,
 			lp_servicename(talloc_tos(), snum),
 			current_user_info.unix_name,
 			"",
@@ -2199,7 +2199,7 @@ static bool print_job_delete1(struct tevent_context *ev,
 	{
 		result = (*(current_printif->job_delete))(
 			lp_printername(talloc_tos(), snum),
-			lp_lprm_command(talloc_tos(), snum),
+			lp_lprm_command(snum),
 			pjob);
 
 		/* Delete the tdb entry if the delete succeeded or the job hasn't
@@ -2819,7 +2819,7 @@ WERROR print_job_start(const struct auth_session_info *server_info,
 		       struct spoolss_DeviceMode *devmode, uint32_t *_jobid)
 {
 	uint32_t jobid;
-	char *path;
+	char *path, *userstr;
 	struct printjob pjob;
 	const char *sharename = lp_const_servicename(snum);
 	struct tdb_print_db *pdb = get_print_db_byname(sharename);
@@ -2866,12 +2866,17 @@ WERROR print_job_start(const struct auth_session_info *server_info,
 
 	fstrcpy(pjob.clientmachine, clientmachine);
 
-	fstrcpy(pjob.user, lp_printjob_username(snum));
-	standard_sub_advanced(sharename, server_info->unix_info->sanitized_username,
+	userstr = talloc_sub_advanced(talloc_tos(), sharename, server_info->unix_info->sanitized_username,
 			      path, server_info->unix_token->gid,
 			      server_info->unix_info->sanitized_username,
 			      server_info->info->domain_name,
-			      pjob.user, sizeof(pjob.user));
+			      lp_printjob_username(snum));
+	if (userstr == NULL) {
+		fstrcpy(pjob.user, lp_printjob_username(snum));
+	} else {
+		strlcpy(pjob.user, userstr, sizeof(pjob.user));
+		TALLOC_FREE(userstr);
+	}
 
 	fstrcpy(pjob.queuename, lp_const_servicename(snum));
 
@@ -3020,7 +3025,7 @@ NTSTATUS print_job_end(struct messaging_context *msg_ctx, int snum,
 
 	/* don't strip out characters like '$' from the printername */
 	lpq_cmd = talloc_string_sub2(tmp_ctx,
-				     lp_lpq_command(talloc_tos(), snum),
+				     lp_lpq_command(snum),
 				     "%p",
 				     lp_printername(talloc_tos(), snum),
 				     false, false, false);
@@ -3028,7 +3033,7 @@ NTSTATUS print_job_end(struct messaging_context *msg_ctx, int snum,
 		status = NT_STATUS_PRINT_CANCELLED;
 		goto fail;
 	}
-	lpq_cmd = talloc_sub_advanced(tmp_ctx,
+	lpq_cmd = talloc_sub_advanced_only(tmp_ctx,
 				      lp_servicename(talloc_tos(), snum),
 				      current_user_info.unix_name,
 				      "",
diff --git a/source3/utils/testparm.c b/source3/utils/testparm.c
index efa58a6a417..a2eabaf33e4 100644
--- a/source3/utils/testparm.c
+++ b/source3/utils/testparm.c
@@ -611,7 +611,7 @@ static void do_per_share_checks(int s)
 			"excludes octal 010 (S_IXGRP).\n\n",
 			lp_servicename(talloc_tos(), s));
 	}
-	if (lp_printing(s) == PRINT_CUPS && *(lp_print_command(talloc_tos(), s)) != '\0') {
+	if (lp_printing(s) == PRINT_CUPS && *(lp_print_command(s)) != '\0') {
 		fprintf(stderr,
 			"Warning: Service %s defines a print command, but "
 			"parameter is ignored when using CUPS libraries.\n\n",