c# - Calling an ASP.NET asmx Soap webservice with raw GET: problem with double type -

I have an asmx webservice that will give me value of 0.05. I want to test the Firefox addon poster with it, everything except the type conversion as a server copy is OK:

  can not convert to 0.05.0.05 System.Double parameter name: Type --- & gt; Input string was not in a correct format.  

Where do I accept conversion in my C # method? Am I forced to use string type in this method if I want to author both posts and GTs?