Thanks for all answers.

the entire deadlock graph in XML format(sql server version: 2005):

<deadlock-list>

<deadlock victim="processabb018">

<process-list>

<process id="processaba7a8" taskpriority="0" logused="59140" waitresource="KEY: 6:72057594059882496 (f10173fc945f)" waittime="8156" ownerId="3209289133"

transactionname="user_transaction"...