Alright I guess I can just do this.....

#!/usr/bin/perl -w

#move to the right directory
system("cd /cd /usr/local/sendmail/smmstore-1.0.0/sbin ./msadm_tclsh")

#set the domain
system("domain_set houston.westerngeco.slb.com")

#add the user
system("mbox_user_add jdoeusr")

open  (IN,  "<users.txt" ) || die ("Cant open users.txt");

 while(<IN>) {
  chomp;
  system("mbox_user_add $_");
}
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