Message Oracle PGA-20966 - syncpoint error: sent string, expecting string, received string

ERROR	syncpoint error: sent string, expecting string, received string
CAUSE	During the processing of a 2-phase commit, an incorrect response was received from the remote transaction program following a syncpoint control command . The expected response was .
ACTION	This is an error in the remote transaction program or the remote OLTP. Check the remote system for error messages from the OLTP. Contact the system administrator for the remote system to assist in problem determination.