Hey forum. I'm receiving the "contains unauthenticated content" SSL warning on my site, but only in my WHMCS installation.

I'm pretty new to WHMCS and tbh, SSL's as well,and I'm having trouble pinpointing the cause of the warning. If anyone could help that would be great.

https://www.doverhost.com.au/ <- root with SSL, this works fine, but not what I need SSL for.
https://www.doverhost.com.au/clients <- WHMCS installation. not so fine

Besides the whole transmitting data securely reason behind using SSL I'd really like to get it showing the blue bar again as that's what customers look for. As far as I can tell I'm using relative paths in the client area but something may be wrong I'm sure.