I just tried to compile sqlrelay-0.50 on RedHat 6.1 (I installed rudiments 0.41-1 first successfully):

libtool: compile:  g++ -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -Wall -pipe -Wno-long-double -Werror -DDEFAULT_CONFIG_FILE=\"/etc/sqlrelay.conf\" -DSYSTEM_SQLRSHRC=\"/etc/sqlrsh\" -I./ -I../../ -I../../src/common -I../../src/util -I../../src/server -I../../src/api/c++/include -c sqlrsh.cpp  -fPIC -DPIC -o .libs/sqlrsh.o
cc1plus: warnings being treated as errors
sqlrsh.cpp: In member function 'void sqlrsh::execute(int, const char**)':
sqlrsh.cpp:1572: error: 'filename' may be used uninitialized in this function
At global scope:
cc1plus: error: unrecognized command line option "-Wno-long-double"
make[2]: *** [sqlrsh.lo] Error 1
make[2]: Leaving directory `/root/rpmbuild/BUILD/sqlrelay-0.50/src/cmdline'
make[1]: *** [all] Error 2
make[1]: Leaving directory `/root/rpmbuild/BUILD/sqlrelay-0.50/src'
make: *** [all] Error 2
error: Bad exit status from /var/tmp/rpm-tmp.DBkPfW (%build)

I'm using a shell script like this to build the RPMs:

rpmbuild -ta \
           -without db2 \
           -without erlang \
           -without freetds \
           -without firebird \
           -without odbc \
           -without ruby \
           -without sqlite \
           -without sybase \
           -without mdbtools \
           -without tcl \
           -without zope \
           -without gtk \
           -with oracle-instant-client-prefix=/usr \

Any ideas? Apologies if this has already been reported, I haven't been able to keep up with the mailing list recently.