Hi,
while I don't know the answer to your question; It should be fairly easy to at least try some different versions?
using the svn co command, you could grab some different versions and put your systelcfg file into the configs directory (modifying it and the pysource file slightly, as the root ($HOMETEL) will be different.
svn co --username ot-svn-public --password telemac1* http://svn.opentelemac.org/svn/opentelemac/tags/v7p3r1
svn co --username ot-svn-public --password telemac1* http://svn.opentelemac.org/svn/opentelemac/tags/v8p0r2/
Worth a go perhaps?
Could you post what O/S this is on out of curiosity. I too am having a few issues compiling Telemac.