Linux beijing 2.6.18-53.el5 #1 SMP Wed Oct 10 16:34:19 EDT 2007 x86_64 x86_64 x86_64 GNU/Linux
./configure --prefix=/usr/rcf --disable-iconv --disable-debug
/usr/rcf/bin/rsync: error while loading shared libraries: libiconv.so.2: cannot open shared object file: No such file or directory
The --disable-iconv's purpose is to turn off the --iconv option (as ./configure --help states). It does not disable all use of iconv_open(), since rsync still wants a good way to figure out what characters may be output to the user in a legible manner.
I have added the configure option --disable-iconv-open, which disables all use of iconv_open(). That will (of course) also disable --iconv.
Ideally, it would be better to figure out why configure believes that iconv_open() exists in your environment, yet rsync can't use it. If you could discover what that disconnect is, please let me know.