Check the following threads:
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=5065000000080000007A140000&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=506500000008000000631C0000&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0
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