Ah-ha! Thanks, nardo, looking out the ldd output was just what I needed to get me thinking correctly about the problem. Sure, I set LD_LIBRARY_PATH, which allows me to compile and link, but that doesn't help the postmaster daemon find the file! Setting LD_LIBRARY_PATH in my database daemon start script solved the problem.

$ ldd /usr/lib/plperl.so
        /usr/gamesparlor/lib/perl5/5.6.0/i686-linux/auto/Opcode/Opcode
+.so => /usr/gamesparlor/lib/perl5/5.6.0/i686-linux/auto/Opcode/Opcode
+.so (0x40006000)
        libperl.so => /usr/lib/libperl.so (0x40013000)
        libc.so.6 => /lib/libc.so.6 (0x400ce000)
        /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x80000000)

$ ldd /usr/gamesparlor/lib/perl5/5.6.0/i686-linux/CORE/libperl.so 
        libc.so.6 => /lib/libc.so.6 (0x400c4000)
        /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x80000000)
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Okay, now if I remove /usr/lib/libperl.so I can get:

$ ldd /usr/lib/plperl.so
        /usr/gamesparlor/lib/perl5/5.6.0/i686-linux/auto/Opcode/Opcode
+.so => /usr/gamesparlor/lib/perl5/5.6.0/i686-linux/auto/Opcode/Opcode
+.so (0x40006000)
        libperl.so => /usr/gamesparlor/lib/perl5/5.6.0/i686-linux/CORE
+/libperl.so (0x4000b000)
        libc.so.6 => /lib/libc.so.6 (0x400ce000)
        /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x80000000)
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but when I try to use a plperl function I get:

SELECT totalcomp(5,6);
ERROR:  Load of file /usr/lib/plperl.so failed: libperl.so: cannot ope
+n shared object file: No such file or directory
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