dojo.string errors after mojo/dojo upgrade

[atlguy]

After upgrading to dojo 1.4 and mojo 1.1.4, I'm seeing errors with the
mojo.helper.Validation. Any validation rule that I set up to use
isRequired returns an error of dojo.string is undefined, referring to
this line of javascript in mojo.js:

if (dojo.isString(value)) return dojo.string.trim(value).length > 0;

If I remove all of my isRequired rules and keep my isType rules, I get
the following error:

Error: requestObj.invocation.proceed is not a function,
referring to this line: requestObj.invocation.proceed();
in stdlib.command.ValidateRulesCommand.

I'm not 100% sure if there is a bug inside of mojo that is creating
this.

Anyone have any ideas?

[atlguy]

I think I found the problem.

I changed

if (dojo.isString(value)) return dojo.string.trim(value).length > 0;

to
if (dojo.isString(value)) return dojo.trim(value).length > 0;

and the first error seems to be gone now.