IDX5 - System is not a central XI; cannot start program

hi all -

Did anyone come across this error message - "System is not a central XI; cannot start program" when trying to execute the tcode - IDX5 on the XI box?

I pushed an IDOC - MATMAS05 from IDOC to XI. It doesn't come into XI.

1. I checked the SM58 on the R/3 side. No Messages.

2. I checked the IDX5 transaction on the XI side, that's when i get the above error message.

3. I checked the IDX2 transaction on the XI side, i get this error "I:000" - Anyone knows what it means?

4. SXMB_MONI doesn't show up anything.

5. R/3 - pushed idocs shows a status of 3.

Any ideas where to look for and how to solve the problem -IDX5 and IDX2.

Environment:

1. We are using SAP NW 2004s

2. SAP BASIS Component - SAP_BASIS - Release 7.00

Thanks in advance,

Tirumal