Place ham in 1 1/2 -quart casserole.
Combine sugar and corn starch in 1-quart measure.
Drain juice from pineapple tidbits into sugar mixture.
Stir in mustard, vinegar and water.
Pour over ham.
Microwave 4 to 6 minutes on HIGH, or until sauce is thickened.
Stir in pineapple.
Microwave 1 minute on HIGH.
Stir in salt.
Serve over cooked rice.