Installing RT on Debian today I got into a bit of a CPAN dependacy loop with the make fixdeps tool 
I eventually tracked it down to the URI module.
Basically the URI module fails to install because of :
t/heuristic……FAILED test 6
On doing some digging this was to do with checking correct name resolution and looking for a picture of a camel on the perl site (you can’t make this stuff up 
).
At the moment something is a bit screwy and this test is currently failing but it is not a big issue for correct operation. The simple work around is to attempt to install it ( cpan URI ) wait for it to barf and then pop into /etc/resolv.conf comment out your nameservers, rerun cpan URI and it will install correctly (remember to uncomment your name servers again in resolv.conf!
Now to get the rest of it up again
Oh BTW I installed XML::RSS and DBD::mysql via apt-get in the end