Time-out occurred while waiting for buffer latch in Sql server 2008 when executing large MERGE query

In our datawarehouse we execute a MERGE query in a storedprocedure in order to synchronize our datawarehouse every night.

Our database server is running Sql-server 2008

During the execution of the stored procedure we receive te following exception:

java.sql.SQLException:Time-out occurred while waiting for buffer latch type 4 for page (1:3939774), database ID 17.

In the eventlog we see several messages with the following format:

Type gebeurtenis:    Informatie
Bron van gebeurtenis:    MSSQLSERVER
Categorie van gebeurtenis:    Server 
Gebeurtenis-id    833
Datum:        28-9-2010
Tijd:        4:14:58
Gebruiker:        n.v.t.
Computer:    AS3
Beschrijving:
SQL Server has encountered 53 occurrence(s) of I/O requests taking longer than 15 seconds to complete on file [D:\SQLDATA\VHDWH_Heezik2.mdf] in database [VHDWH_Heezik2] (17).  The OS file handle is 0x000004DC.  The offset of the latest long I/O is: 0x000006a1cdc000

Zie Help en ondersteuning op http://go.microsoft.com/fwlink/events.asp voor meer informatie.
Gegevens:
0000: 41 03 00 00 0a 00 00 00   A.......
0008: 04 00 00 00 41 00 53 00   ....A.S.
0010: 33 00 00 00 00 00 00 00   3.......

What does this mean and what actions should we take to resolve this problem?

Note: I am a developer and not a system administrator, so I don't know what information is needed to answer this question.

This might help: http://support.microsoft.com/kb/968543