I dont think there is a OOB way to that.
may be locate the same grammar file on the fileserver, and update it manually, also on the "scripts" directory on apsperver installation path, The appserver should be restarted, it does cache some grammar files.
Havent done this since 7.6 ! , not tried on 8.x
In a side box I found a link (which I couldn't find through the search-function before) referring to the right solution:
Quoted here for reference:
Delete deleteModelObjectAndDependentObjects 600 KEY_FROM_FIRST_COMMAND
So Bill, if you just answer to this thread - you will get the points ;-)