There is no-one who could give a sensible answer to your question with this little information. Your title is that the GD module stops working. I find that hard to believe.
I think it would be best if you'd post the code, the exact errormessage and the perlversion you are using.
Jouke Visser, Perl 'Adept'
Using Perl to help the disabled: pVoice and pStory