spamassassin problem and question

[David Banning]

While spamassassin is executing I am getting this error;

Can't locate Razor2/Client/Agent.pm in @INC (@INC contains: /usr/local/lib/perl5/site_perl/5.8.7 ../lib /usr/local/lib/perl5/5.8.7/BSDPAN /usr/local/lib/perl5/site_perl/5.8.7/mach /usr/local/lib/perl5/site_perl/5.8.6 /usr/local/lib/perl5/site_perl/5.005 /usr/local/lib/perl5/site_perl /usr/local/lib/perl5/5.8.7/mach /usr/local/lib/perl5/5.8.7) at /usr/local/lib/perl5/site_perl/5.8.7/Mail/SpamAssassin/Plugin/Razor2.pm line 70. 

So I look for the file;

# locate Agent.pm
/usr/local/lib/perl5/site_perl/5.005/Sitescooper/UserAgent.pm
/usr/local/lib/perl5/site_perl/5.005/i386-freebsd/Razor2/Client/Agent.pm
/usr/local/lib/perl5/site_perl/5.8.7/LWP/UserAgent.pm

In my simplistic way of attempting resolution, I am thinking 
of just adding /usr/local/lib/perl5/site_perl/5.005/i386-freebsd
to @INC - but here is where my knowledge runs out. Where are the
references to directories referred to as @INC stored? 
@INC does not appear to be a file.

I may even be attempting to solve this incorrectly. Any pointers
would be useful -
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