Solaris has md5 implementation conforming to rfc-1321.
There is a name clash got failing on T4 (sun4v) systems.


--- samba-3.6.6/source3/Makefile.in	Sun Jun 24 10:21:16 2012
+++ a/source3/Makefile.in	Tue Jul 10 06:46:18 2012
@@ -430,7 +430,7 @@
 		   ../lib/util/blocking.o ../lib/util/rfc1738.o \
 		   ../lib/util/select.o ../lib/util/util_pw.o
 
-CRYPTO_OBJ = ../lib/crypto/crc32.o ../lib/crypto/md5.o \
+CRYPTO_OBJ = ../lib/crypto/crc32.o @CRYPTO_MD5_OBJ@ \
 			 ../lib/crypto/hmacmd5.o ../lib/crypto/arcfour.o \
 			 ../lib/crypto/md4.o \
 			 ../lib/crypto/sha256.o ../lib/crypto/hmacsha256.o \
--- samba-3.6.6/source3/configure.in	Sun Jun 24 10:21:16 2012
+++ a/source3/configure.in	Tue Jul 10 08:59:06 2012
@@ -751,6 +751,25 @@
 AC_CHECK_HEADERS(netgroup.h)
 AC_CHECK_HEADERS(linux/falloc.h)
 
+dnl check for OS implementation of md5 conformant to rfc1321
+AC_CHECK_HEADERS(md5.h)
+if test x"$ac_cv_header_md5_h" = x"yes"; then
+	AC_DEFINE(HAVE_MD5_H, 1,
+		[Whether md5.h is available.])
+	AC_CHECK_LIB(md5, MD5Update,
+	    [
+		LIBS="${LIBS} -lmd5"
+		CRYPTO_MD5_OBJ=
+		AC_DEFINE(HAVE_LIBMD5, 1,
+		    [Whether libmd5 conformant to rfc1321 is available.])],
+	    [
+		CRYPTO_MD5_OBJ="../lib/crypto/md5.o"])
+else
+	CRYPTO_MD5_OBJ="../lib/crypto/md5.o"
+fi
+AC_SUBST(CRYPTO_MD5_OBJ)
+
+
 AC_CHECK_HEADERS(rpcsvc/yp_prot.h,,,[[
 #if HAVE_RPC_RPC_H
 #include <rpc/rpc.h>
--- samba-3.6.6/lib/crypto/md5.h	Sun Jun 24 10:21:16 2012
+++ a/lib/crypto/md5.h	Tue Jul 10 11:33:09 2012
@@ -5,11 +5,21 @@
 #define HEADER_MD5_H 
 #endif
 
+#ifdef HAVE_MD5_H
+/*
+ * Try to avoid clashes with Solaris MD5 implementation.
+ * ...where almost all implementations follows:
+ * "Schneier's Cryptography Classics Library"
+ */
+#include <md5.h>
+#else
+
 struct MD5Context {
 	uint32_t buf[4];
 	uint32_t bits[2];
 	uint8_t in[64];
 };
+typedef struct MD5Context MD5_CTX;
 
 void MD5Init(struct MD5Context *context);
 void MD5Update(struct MD5Context *context, const uint8_t *buf,
@@ -16,4 +26,6 @@
 	       size_t len);
 void MD5Final(uint8_t digest[16], struct MD5Context *context);
 
+#endif /* !HAVE_MD5_H */
+
 #endif /* !MD5_H */
--- samba-3.6.6/lib/crypto/hmacmd5.h	Sun Jun 24 10:21:16 2012
+++ a/lib/crypto/hmacmd5.h	Tue Jul 10 12:20:30 2012
@@ -25,7 +25,7 @@
 
 typedef struct 
 {
-        struct MD5Context ctx;
+	MD5_CTX ctx;
         uint8_t k_ipad[65];    
         uint8_t k_opad[65];
 
--- samba-3.6.6/lib/crypto/hmacmd5.c	Sun Jun 24 10:21:16 2012
+++ a/lib/crypto/hmacmd5.c	Tue Jul 10 10:02:50 2012
@@ -36,7 +36,7 @@
         /* if key is longer than 64 bytes reset it to key=MD5(key) */
         if (key_len > 64)
 	{
-                struct MD5Context tctx;
+		MD5_CTX tctx;
 
                 MD5Init(&tctx);
                 MD5Update(&tctx, key, key_len);
@@ -91,7 +91,7 @@
 ***********************************************************************/
 _PUBLIC_ void hmac_md5_final(uint8_t *digest, HMACMD5Context *ctx)
 {
-        struct MD5Context ctx_o;
+	MD5_CTX ctx_o;
 
         MD5Final(digest, &ctx->ctx);          
 
--- samba-3.6.6/lib/crypto/md5test.c	Sun Jun 24 10:21:16 2012
+++ a/lib/crypto/md5test.c	Tue Jul 10 12:24:05 2012
@@ -63,7 +63,7 @@
 	};
 
 	for (i=0; i < ARRAY_SIZE(testarray); i++) {
-		struct MD5Context ctx;
+		MD5_CTX ctx;
 		uint8_t md5[16];
 		int e;
 
--- samba-3.6.6/source3/modules/vfs_streams_xattr.c	Sun Jun 24 10:21:16 2012
+++ a/source3/modules/vfs_streams_xattr.c	Tue Jul 10 12:25:37 2012
@@ -39,7 +39,7 @@
 
 static SMB_INO_T stream_inode(const SMB_STRUCT_STAT *sbuf, const char *sname)
 {
-	struct MD5Context ctx;
+	MD5_CTX ctx;
         unsigned char hash[16];
 	SMB_INO_T result;
 	char *upper_sname;
--- samba-3.6.6/source3/libsmb/smb_signing.c	Sun Jun 24 10:21:16 2012
+++ a/source3/libsmb/smb_signing.c	Tue Jul 10 12:26:27 2012
@@ -137,7 +137,7 @@
 {
 	const size_t offset_end_of_sig = (smb_ss_field + 8);
 	uint8_t sequence_buf[8];
-	struct MD5Context md5_ctx;
+	MD5_CTX md5_ctx;
 
 	/*
 	 * Firstly put the sequence number into the first 4 bytes.
--- samba-3.6.6/source3/libsmb/ntlmssp.c	Sun Jun 24 10:21:16 2012
+++ a/source3/libsmb/ntlmssp.c	Tue Jul 10 12:27:10 2012
@@ -612,7 +612,7 @@
 			return NT_STATUS_NO_MEMORY;
 		}
 	} else if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
-		struct MD5Context md5_session_nonce_ctx;
+		MD5_CTX md5_session_nonce_ctx;
 		uint8_t session_nonce[16];
 		uint8_t session_nonce_hash[16];
 		uint8_t user_session_key[16];
--- samba-3.6.6/source3/web/swat.c	Sun Jun 24 10:21:16 2012
+++ a/source3/web/swat.c	Tue Jul 10 12:27:44 2012
@@ -151,7 +151,7 @@
 void get_xsrf_token(const char *username, const char *pass,
 		    const char *formname, time_t xsrf_time, char token_str[33])
 {
-	struct MD5Context md5_ctx;
+	MD5_CTX md5_ctx;
 	uint8_t token[16];
 	int i;
 
--- samba-3.6.6/source3/rpc_client/init_samr.c	Sun Jun 24 10:21:16 2012
+++ a/source3/rpc_client/init_samr.c	Tue Jul 10 12:28:25 2012
@@ -34,7 +34,7 @@
 	/* samr_CryptPasswordEx */
 
 	uchar pwbuf[532];
-	struct MD5Context md5_ctx;
+	MD5_CTX md5_ctx;
 	uint8_t confounder[16];
 	DATA_BLOB confounded_session_key = data_blob(NULL, 16);
 
--- samba-3.6.6/libcli/auth/smbencrypt.c	Sun Jun 24 10:21:16 2012
+++ a/libcli/auth/smbencrypt.c	Tue Jul 10 12:33:08 2012
@@ -99,7 +99,7 @@
 
 void E_md5hash(const uint8_t salt[16], const uint8_t nthash[16], uint8_t hash_out[16])
 {
-	struct MD5Context tctx;
+	MD5_CTX tctx;
 	MD5Init(&tctx);
 	MD5Update(&tctx, salt, 16);
 	MD5Update(&tctx, nthash, 16);
@@ -623,7 +623,7 @@
 
 void encode_or_decode_arc4_passwd_buffer(unsigned char pw_buf[532], const DATA_BLOB *psession_key)
 {
-	struct MD5Context tctx;
+	MD5_CTX tctx;
 	unsigned char key_out[16];
 
 	/* Confounder is last 16 bytes. */
@@ -703,7 +703,7 @@
 					struct wkssvc_PasswordBuffer **pwd_buf)
 {
 	uint8_t buffer[516];
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 	struct wkssvc_PasswordBuffer *my_pwd_buf = NULL;
 	DATA_BLOB confounded_session_key;
 	int confounder_len = 8;
@@ -741,7 +741,7 @@
 					  char **pwd)
 {
 	uint8_t buffer[516];
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 	size_t pwd_len;
 
 	DATA_BLOB confounded_session_key;
--- samba-3.6.6/libcli/auth/schannel_sign.c	Sun Jun 24 10:21:16 2012
+++ a/libcli/auth/schannel_sign.c	Tue Jul 10 12:36:36 2012
@@ -110,7 +110,7 @@
 {
 	uint8_t packet_digest[16];
 	static const uint8_t zeros[4];
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 
 	MD5Init(&ctx);
 	MD5Update(&ctx, zeros, 4);
--- samba-3.6.6/libcli/auth/ntlmssp_server.c	Sun Jun 24 10:21:16 2012
+++ a/libcli/auth/ntlmssp_server.c	Tue Jul 10 12:38:03 2012
@@ -359,7 +359,7 @@
 	*/
 	if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 		if (ntlmssp_state->nt_resp.length == 24 && ntlmssp_state->lm_resp.length == 24) {
-			struct MD5Context md5_session_nonce_ctx;
+			MD5_CTX md5_session_nonce_ctx;
 			state->doing_ntlm2 = true;
 
 			memcpy(state->session_nonce, ntlmssp_state->internal_chal.data, 8);
--- samba-3.6.6/libcli/auth/ntlmssp_sign.c	Sun Jun 24 10:21:16 2012
+++ a/libcli/auth/ntlmssp_sign.c	Tue Jul 10 12:39:59 2012
@@ -51,7 +51,7 @@
 			    DATA_BLOB session_key,
 			    const char *constant)
 {
-	struct MD5Context ctx3;
+	MD5_CTX ctx3;
 	MD5Init(&ctx3);
 	MD5Update(&ctx3, session_key.data, session_key.length);
 	MD5Update(&ctx3, (const uint8_t *)constant, strlen(constant)+1);
--- samba-3.6.6/libcli/auth/credentials.c	Sun Jun 24 10:21:16 2012
+++ a/libcli/auth/credentials.c	Tue Jul 10 12:43:38 2012
@@ -69,7 +69,7 @@
 {
 	unsigned char zero[4], tmp[16];
 	HMACMD5Context ctx;
-	struct MD5Context md5;
+	MD5_CTX md5;
 
 	ZERO_STRUCT(creds->session_key);
 
--- samba-3.6.6/libcli/drsuapi/repl_decrypt.c	Sun Jun 24 10:21:16 2012
+++ a/libcli/drsuapi/repl_decrypt.c	Tue Jul 10 12:45:40 2012
@@ -39,7 +39,7 @@
 	DATA_BLOB confounder;
 	DATA_BLOB enc_buffer;
 
-	struct MD5Context md5;
+	MD5_CTX md5;
 	uint8_t _enc_key[16];
 	DATA_BLOB enc_key;
 
@@ -198,7 +198,7 @@
 	DATA_BLOB rid_crypt_out = data_blob(NULL, 0);
 	DATA_BLOB confounder;
 
-	struct MD5Context md5;
+	MD5_CTX md5;
 	uint8_t _enc_key[16];
 	DATA_BLOB enc_key;
 
--- samba-3.6.6/source4/libcli/raw/smb_signing.c	Sun Jun 24 10:21:16 2012
+++ a/source4/libcli/raw/smb_signing.c	Tue Jul 10 13:27:44 2012
@@ -103,7 +103,7 @@
 void sign_outgoing_message(struct smb_request_buffer *out, DATA_BLOB *mac_key, unsigned int seq_num) 
 {
 	uint8_t calc_md5_mac[16];
-	struct MD5Context md5_ctx;
+	MD5_CTX md5_ctx;
 
 	/*
 	 * Firstly put the sequence number into the first 4 bytes.
@@ -138,7 +138,7 @@
 	uint8_t calc_md5_mac[16];
 	uint8_t *server_sent_mac;
 	uint8_t sequence_buf[8];
-	struct MD5Context md5_ctx;
+	MD5_CTX md5_ctx;
 	const size_t offset_end_of_sig = (HDR_SS_FIELD + 8);
 	int i;
 	const int sign_range = 0;
--- samba-3.6.6/source4/ntp_signd/ntp_signd.c	Sun Jun 24 10:21:16 2012
+++ a/source4/ntp_signd/ntp_signd.c	Tue Jul 10 13:29:16 2012
@@ -107,7 +107,7 @@
 	enum ndr_err_code ndr_err;
 	struct ldb_result *res;
 	const char *attrs[] = { "unicodePwd", "userAccountControl", "cn", NULL };
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 	struct samr_Password *nt_hash;
 	uint32_t user_account_control;
 	int ret;
--- samba-3.6.6/source4/libnet/libnet_passwd.c	Sun Jun 24 10:21:16 2012
+++ a/source4/libnet/libnet_passwd.c	Tue Jul 10 13:30:45 2012
@@ -274,7 +274,7 @@
 	DATA_BLOB session_key;
 	DATA_BLOB confounded_session_key = data_blob_talloc(mem_ctx, NULL, 16);
 	uint8_t confounder[16];	
-	struct MD5Context md5;
+	MD5_CTX md5;
 
 	if (r->samr_handle.in.info21) {
 		return NT_STATUS_INVALID_PARAMETER_MIX;
@@ -330,7 +330,7 @@
 	DATA_BLOB session_key;
 	DATA_BLOB confounded_session_key = data_blob_talloc(mem_ctx, NULL, 16);
 	uint8_t confounder[16];	
-	struct MD5Context md5;
+	MD5_CTX md5;
 
 	if (!r->samr_handle.in.info21) {
 		return NT_STATUS_INVALID_PARAMETER_MIX;
--- samba-3.6.6/source4/torture/ntp/ntp_signd.c	Sun Jun 24 10:21:16 2012
+++ a/source4/torture/ntp/ntp_signd.c	Tue Jul 10 13:32:00 2012
@@ -78,7 +78,7 @@
 	char *unix_address;
 	int sys_errno;
 
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 	uint8_t sig[16];
 	enum ndr_err_code ndr_err;
 	bool ok;
--- samba-3.6.6/source4/torture/rpc/samr.c	Sun Jun 24 10:21:16 2012
+++ a/source4/torture/rpc/samr.c	Tue Jul 10 13:33:48 2012
@@ -771,7 +771,7 @@
 	uint8_t confounder[16];
 	char *newpass;
 	struct dcerpc_binding_handle *b = p->binding_handle;
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 	struct samr_GetUserPwInfo pwp;
 	struct samr_PwInfo info;
 	int policy_min_pw_len = 0;
@@ -856,7 +856,7 @@
 	bool ret = true;
 	DATA_BLOB session_key;
 	DATA_BLOB confounded_session_key = data_blob_talloc(tctx, NULL, 16);
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 	uint8_t confounder[16];
 	char *newpass;
 	struct dcerpc_binding_handle *b = p->binding_handle;
@@ -1140,7 +1140,7 @@
 	bool ret = true;
 	DATA_BLOB session_key;
 	DATA_BLOB confounded_session_key = data_blob_talloc(tctx, NULL, 16);
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 	uint8_t confounder[16];
 	char *newpass;
 	struct dcerpc_binding_handle *b = p->binding_handle;
@@ -2458,7 +2458,7 @@
 	DATA_BLOB session_key;
 	DATA_BLOB confounded_session_key = data_blob_talloc(tctx, NULL, 16);
 	uint8_t confounder[16];
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 
 	bool ret = true;
 	struct lsa_String server, account;
--- samba-3.6.6/source4/torture/rpc/samba3rpc.c	Sun Jun 24 10:21:16 2012
+++ a/source4/torture/rpc/samba3rpc.c	Tue Jul 10 13:34:47 2012
@@ -774,7 +774,7 @@
 		DATA_BLOB session_key;
 		DATA_BLOB confounded_session_key = data_blob_talloc(
 			mem_ctx, NULL, 16);
-		struct MD5Context ctx;
+		MD5_CTX ctx;
 		uint8_t confounder[16];
 
 		ZERO_STRUCT(u_info);
--- samba-3.6.6/source4/torture/rpc/samlogon.c	Sun Jun 24 10:21:16 2012
+++ a/source4/torture/rpc/samlogon.c	Tue Jul 10 13:36:41 2012
@@ -1075,7 +1075,7 @@
 	uint8_t session_nonce_hash[16];
 	uint8_t client_chall[8];
 
-	struct MD5Context md5_session_nonce_ctx;
+	MD5_CTX md5_session_nonce_ctx;
 	HMACMD5Context hmac_ctx;
 
 	ZERO_STRUCT(user_session_key);
--- samba-3.6.6/source4/auth/credentials/credentials_ntlm.c	Sun Jun 24 10:21:16 2012
+++ a/source4/auth/credentials/credentials_ntlm.c	Tue Jul 10 13:38:44 2012
@@ -110,7 +110,7 @@
 		/* LM Key is incompatible... */
 		*flags &= ~CLI_CRED_LANMAN_AUTH;
 	} else if (*flags & CLI_CRED_NTLM2) {
-		struct MD5Context md5_session_nonce_ctx;
+		MD5_CTX md5_session_nonce_ctx;
 		uint8_t session_nonce[16];
 		uint8_t session_nonce_hash[16];
 		uint8_t user_session_key[16];
--- samba-3.6.6/source4/dsdb/samdb/ldb_modules/password_hash.c	Sun Jun 24 10:21:16 2012
+++ a/source4/dsdb/samdb/ldb_modules/password_hash.c	Tue Jul 10 13:40:01 2012
@@ -1351,7 +1351,7 @@
 	}
 
 	for (i=0; i < ARRAY_SIZE(wdigest); i++) {
-		struct MD5Context md5;
+		MD5_CTX md5;
 		MD5Init(&md5);
 		if (wdigest[i].nt4dom) {
 			MD5Update(&md5, wdigest[i].nt4dom->data, wdigest[i].nt4dom->length);
--- samba-3.6.6/source4/rpc_server/samr/samr_password.c	Sun Jun 24 10:21:16 2012
+++ a/source4/rpc_server/samr/samr_password.c	Tue Jul 10 13:42:32 2012
@@ -544,7 +544,7 @@
 	DATA_BLOB new_password;
 	DATA_BLOB co_session_key;
 	DATA_BLOB session_key = data_blob(NULL, 0);
-	struct MD5Context ctx;
+	MD5_CTX ctx;
 
 	nt_status = dcesrv_fetch_session_key(dce_call->conn, &session_key);
 	if (!NT_STATUS_IS_OK(nt_status)) {