regardin linked servers, when i ran the linked server query i got the error : No transaction is active,Msg 7391, Level 16, State 2, Line 177?

Hi All,

i created a linked server beetween sql server 2005( windows 2003 cluster) and sql server 2008r2(windows 2008 cluster), both are in cluser. after that test connection and select query was running successfully, but when i ran the update query in sql server 2005, i got the below error,
OLE DB provider
"SQLNCLI" for linked server "xxx/instance2" returned
message"No transaction is active.".

Msg 7391, Level 16, State 2, Line 177

The operation could not be performed because OLE DB provider "SQLNCLI" for linked server "xxx/instance2" wasunable to begin a
distributed transaction

please any one suggest the solution for the above problem, it's urgent...

Thank you in Advance,

rup

rup