The following text contains error.

<realm classname="org.apache.catalina.realm.JDBCRealm" debug="99"
drivername="org.gjt.mm.mysql.Driver"
connectionurl="jdbc:mysql://localhost/tomcatusers?user=test;password=test"
usertable="users" usernamecol="user_name" usercredcol="user_pass"
userroletable="user_roles" rolenamecol="role_name"/>

The connection string is incorrect. It should not used ';' but '&apm;' instead.

RP