[Q] using conditionals in rc file

I know this should be easy, but I'm in need of a little help or a
couple of examples.  I want to set the PATH envar based on platform
procmail runs on.

if ( architecture = sunos4-sun4 )
then 
   PATH=/sun4/binaries
elsif ( architecture = netbsd-i386 )
   PATH=/netbsd/binaries
elsif ( architecture = linux-i386 )
   PATH=/linux/binaries
else
   ...

Thanks,
Sam
sam(_at_)Progressive-Systems(_dot_)Com