Then call a script instead.

#!/bin/ksh

LD_LIBRARY_PATH=....
export LD_LIBRARY_PATH
cd /dir/where/you/want/to/start
exec commandtorun param1 param2 ...
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Update: Added exec - saves one process in the process table.

and call it from your crontab instead of the command you are calling right now.

You can also do on the crontab line

0 0 * * * LD_LIBRARY_PATH=foobar commandtorun param1 param2
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Also make certain that you have your CWD properly accounted for from cron. I will often do a cd /dir/to/run/from && command... as part of my cron line.