Getting an error while trying to run a perl script

Hi,
I am trying to run a perl script, and i am encountering an error
that "conn_cache does not find in UserAgent", when i checked the UserAgent.pm file, i found that, conn_cache sub is not available, and then i tried copying that function from some google site and i am unable to do that, getting an error "Access denied", but not sure what was the reason.

Thanks,
Ravi Kiran.