For whatever reason (oversight during overzealous package removal?) it was not included in RHEL3.
you asked this a while ago and someone mentiuoned that it was an acident and put back in update 1. if you 'up2date -i mtx' it be there.
On my fully paid-up subscribed RHEL3 box, I fixed this by recompiling the mtx SRPM from Fedora.
This has worked great until I upgraded to the U3 kernel (2.4.21-20.EL). Now I can no longer use the mtx command.
# mtx -f /dev/sg3 status cannot open SCSI device '/dev/sg3' - No such device or address
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