WCF/Rest/UriTemplate variable length query string parameter list?

Question

WCF will match this:

http://localhost:8888/test/blahFirst/blahSecond/sdfsdf,wwewe

to this:

[OperationContract]
[WebGet( UriTemplate = "test/{first}/{second}/{val1},{val2}" )]
string GetVal( string first, string second, string val1, string val2 );

Is there a way to make the va11, val2 be a variable length list of parameters? So it could be val1, ...., valN? And end up with a service method such as:

string GetVal( string first, string second, List<string> params );

Or something along those lines?