cgi-bin vs. scgi-bin vs. perl

hello.

I am new to Cpanel. In the root directory of each web account, I see directories with these names:

cgi-bin
scgi-bin

While I know what the cgi-bin is for, I am not sure what the scgi-bin is for.


A related question is:

is Mod-perl supported? How do I enable this? Is this a good idea?

I do have trouble because some email forms that I had been using under Ensim prior to migrating to Cpanel are not working. Basically, I click to submit a message, they react but there is no error and no message gets sent. When I try to provoke an erreor by not filling any of the required fields, still no error message. The form simply reacts as if it worked, but no error gets displayed and no message gets sent. I wonder why?

The su exec log shows no error.