org.xmlpull.v1。XmlPullParserException:意外类型(位置:java.io.InputStreamReader@c599f9fd中的END_DOCUMENT null@1:0)

I am new to blackberry , iam just trying to call a Web service that do some operations on SAP CRM , ,but iam getting this exception: org.xmlpull.v1.XmlPullParserException: unexpected type (position:END_DOCUMENT null@1:0 in java.io.InputStreamReader@c599f9fd) I am new to blackberry , iam just trying to cal