Full Name Join Form

I am using Dolphin 6.1.4.

I have a Full Name (two words) login which works well But:

Problem:

When I go to my profile page having used two words (full name) for join/login, my profile page loads but there is no drop down menu. Everything is ok if I login using one word.

Is it possible to fix this or would I be better having First Name & Last Name join/login boxes?

Many thanks for your help,

Stuart

I would appreciate some help on this one. I am hoping to launch my site soonest!!

Regards,

Stuart