Case statement containing a greater than evaluation

 Hi, I am attempting to split the Message column of a Windows event log into two, for import into a database (max literal of 2000). This would require a greater than string length evaluation. The following is not acceptable to Log Parser:

CASE (STRLEN(Message)>2000)
        WHEN True Then SUBSTR(Message, 0, 2000)
        ELSE Message
    END AS Message1,

Any suggestions? 

Thanks.