(fedora core3, mysql 5.0.41-linux-i686, apache)
I have a similar problem...could somebody help me on this
in fact i have updated the config file with the lib directory as wassy121 has mentioned
I get the following error when i access the bugzilla from firefox browser

Software error:

install_driver(mysql) failed: Can't load '/usr/lib/perl5/site_perl/5.8.6/i386-linux-thread-multi/auto/DBD/mysql/mysql.so' for module DBD::mysql: libmysqlclient.so.15: cannot open shared object file: No such file or directory at /usr/lib/perl5/5.8.6/i386-linux-thread-multi/DynaLoader.pm line 230.
at (eval 4 line 3
Compilation failed in require at (eval 4 line 3.
Perhaps a required shared library or dll isn't installed where expected
at Bugzilla/DB.pm line 769

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