SSH/RCP connectivity error

Hi Team,
Hope you will be able to help me out with this problem.
Our sun solaris 9 system receives Idoc files from another xxx system through RCP. But before RCP they establish an SSH connection. Since today morning they are not able to establish connection and is getting an error as pasted below when trying to connect us:
HOST =xx.xx.xx.xxx
PROG =<path>/bin/rcprfcexec.sh
**** Trace file opened at 20091105 124559 GMT, REL 46D,0,2415, VER 3
======> CPIC-CALL: 'ThSAPECMINIT' : cmRc=27 thRc=456
Timeout during connection setup (check that partner exists)
Error RFCIO_ERROR_SYSERROR in abrfcpic.c : 1356
CPIC-CALL: 'ThSAPECMINIT' : cmRc=27 thRc=456
------------------------------------------------------------------------
I am sure there were no changes like patching done to our unix box and no other apparent chages are done by us also. I am unable to figure out the problem for this.

Hopefully you may be able to help me.
Thank you.