Help! :Account Address City, javascript to save as uppercase in the database. not working as expecte

We are trying to force our end users to always have the Account Address City in UPPERCASE.

We need to save the city in UPPERCASE in the database so we can use it to generate a unique location value in the location field by combining it with some addtional field values using a workflow.

We have found a script that is supposed to be doing this but it does not work exactly as expected. The script below almost does what we want, however it only affecting the presentation of the value on the Account Edit form and not the actual value in the database.