As I said I was GUESSING, if you are sure you are communicating with a HTTPS service then sslenabled=true is the correct thing to be doing.
Sorry no further help that I can think of.
Is there anything that you know that HAS changed in your IT infrastructure since this was working (new/changed network rules, new/changed firewalls, new/changed DNS, new/changed versions of Java on your PC (are other PCs OK?) ...... new/changed anything ???)