Use a sap function module webservice in SAP PI

HI,

I'm new to webservices. i wanted to use SAP function module webservice in SAP PI. i'm using a http to SOAP synchronuos senario, m getting a error

" Runtime exception occurred during application mapping com/sap/xi/tf/_MM_SOAP_HTTP_; com.sap.aii.utilxi.misc.api.BaseRuntimeException:The element type "META" must be terminated by thematching end-tag "</META>". "

please let me know what might have gone wrong

Thanks in advance