Webwork - 5:28 pm on Jun 15, 2012 (gmt 0)
Is the hosting company listed in the WhoIs record as the registrant and as the administrative contact?
If so you might have to call and/or send a letter to the administrator explaining the crisis/problem.
You will probably have to offer proof that you are the "owner in fact" of the domain and that you don't owe any money for services, etc.
In a worst case scenario you may have to hire a lawyer/solicitor to present the matter to a court on an emergency basis. In the States that procedure is sometimes called an "Order to Show Cause" (why certain relief should not be granted immediately).