Salary advice...

My apologies if this is covered in a faq somewhere, if there is one I'd be thrilled to read it...

I'm a software engineer(and US citizen) who's been with my company for 15 years and I've grown quite tired of the city I'm currently living in. I'd like to move to Cambridge, UK to work with my extended group there. I've talked with my immediate management and they're agreeable to the idea so I've been slowly going through the process of getting my company to sponsor a visa for me. This is progressing at a glacial pace unfortunately but something that came up last week was that there is a possibility that I'll take a salary hit in the move. It was explained to me that even though the cost of living in the UK is relatively higher, software engineer salaries are relatively less than the US.

This seems a bit hard for me to swallow. I would think that with an international company, the only affect to salary in moving someone from one country to another would be whatever the conversion difference would amount to.

Any thoughts? Of course what I'm wondering is if my company is jerking me around here.

Thanks a bunch!