You can solve this by adding:
<VirtualHost project1.mydomain.com>
....
PerlOptions +Parent
....
</VirtualHost>
<VirtualHost project2.mydomain.com>
....
PerlOptions +Parent
....
</VirtualHost>
http://perl.apache.org/docs/2.0/user/config/config.html#C_Parent_
--
Maxim Nechaev
