unmarried partner to spousal visa?

hey all.
So my boyfriend and I wanted to come back to the UK and work here until his fiance visa for America went through...we intend to settle in America as soon as possible.  I was always advised the fiance visa for the US was the easiest route to take so that is what we did.  In order to be here with him I got the unmarried partner visa.  I have been here a few weeks, got the NI number appt next week etc.

Now the AMerican immigration people are royally screwing up the system for fiance visas with a new law they passed back in March but told no one about til now.  THis means our app for his fiance visa will be severly delayed.  So now we are thinking about getting married now instead and applying for the spousal visa.  My question is:  will anyone here marry me with an unmarried parnter visa?  I dont really care about switching my visa i just would want the marriage certificate to show to america.
thanks a lot for any help anyone can give 

How long is your unmarried partner visa for.  If it is for > 6 months and you have > 6 months left on the visa (which you should, they are good for normally 2 years, right forum)?  Then you should be sucessful in applying for a Certificate of Approval (COA) from the Home Office.  This would allow you to get married in the UK.  Now technically, if you qualify for marrying in the Church of England, you would not need to COA, which is a loophole that government is trying to shut.  I don't know all of the rules for getting married in the CoE, but I assume one or both of you have to be a member.

If you are here on a visitors visa or have less than 6 months left on your visa, your best bet is to leave the country temporarialy and apply for a fiancee visa.  They are a lot more straight forward then US!