error: no match of right hand side value {error,[{exception,{error,"unknown tag: html"}

when use erlsom, following error came.
{'wsdl:tTypes','wsdl:tExtensibleDocumented'}]}
** exception error: no match of right hand side value {error,[{exception,{error,"unknown tag: html"}},
{stack,[undefined]},
{received,{startElement,[],"html",[],[]}}]}

Same WSDL file work with PHP nusoap lib.
Pls help to solve this