Urgent Help, please!

[The Guyver]

Hello there,
I'm in a desperate need to write a PHP script that creates a new mailbox
with vpopmail 4.10.35
I've written everything correctly but when I use exec or system I always end
up with this error:

Error: Unable to chdir to vpopmail/domains directory

please help me it's very urgent if anybody has a clue I'll appreciate so
much.

Guyver