a0d929ca_WSRP_v2_0_Specification__Statement_text
[#] CS157 [Section] 9.2.2.9 [Statement text] 
If the Consumer includes wsrp-portletHandle, wsrp-userContextKey, wsrp-portletInstanceKey, wsrp-sessionID, wsrp-portletStates, or wsrp-pageState in a template, Producer written URLs based on that template MUST replace the specified portlet URL parameter with the value the Consumer separately supplied in a data field.
WSRP v2.0 Specification
Statement text