Short solution.
If you have for example:
[root@server]# suexec -V
-D AP_DOC_ROOT=”/var/www” <<<<<<<<<<<<<<<<<<<<<<<< correct place for suexec scripts
-D AP_GID_MIN=100
-D AP_HTTPD_USER="apache"
-D AP_LOG_EXEC="/var/log/httpd/suexec.log"
-D AP_SAFE_PATH="/usr/local/bin:/usr/bin:/bin"
-D AP_UID_MIN=500
-D AP_USERDIR_SUFFIX="public_html"
[root@server]#
then:
1.) create a directory /var/www/cgi-bin (owner root / chmod 0701)
2.) create a directory /var/www/cgi-bin/YOUR_CUSTOMER (owner YOUR_CUSTOMER / chmod 0701)
3.) add symlink $HOME_of_virtualhost/cgi-bin which points to /var/www/cgi-bin/YOUR_CUSTOMER
4.) add path option which allows executing scripts (perl etc etc) in $HOME_of_virtualhost/cgi-bin
CGI will work.