Should dial like this, not 100% sure though:

011 441 604 232003

This is how it was posted above:
01604 232003

I think the 0 is bogus at the begining, England is always a 1 or a 2 for the first digit. 44 is the country code. I'll check tomorrow at work and get back, Overseas calls are expensive! And don't forget the time difference, they are 6 hours ahead of Central time.

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