Thanks for the reply :) I think I was actually just being a dumb arse!

[Sat Jan 18 16:11:05 2014] test.cgi: Illegal division by zero at /usr/
+lib/perl5/site_perl/5.8.8/Finance/Quote/IndiaMutual.pm line 27.
[Sat Jan 18 16:11:05 2014] test.cgi: Compilation failed in require at 
+(eval 34) line 1.
[Sat Jan 18 16:11:05 2014] test.cgi: BEGIN failed--compilation aborted
+ at (eval 34) line 1.
[Sat Jan 18 16:11:05 2014] test.cgi:  at test.cgi line 45
FOO: 40.565
[download]

The "FOO" bit with the price prints out just fine... so as you said, the debugging coming out in the SSH terminal shouldn't affect it . So in fact, it was actually running just fine... doh!