Task Scheduler - Update custom properties problem

I am able to manually create a custom property, as follows:

Property Name      P_Length

Type                     Text

Text Expression     L@ANGLE     - am referencing a dimension is a file created from a template, (dimension name is therefore consistant)

Evaluated Value     300.9

I am unable to enter the Text Expression L@ANGLE when using the SW Task Scheduler - Update custom properties.

The @ character is the character that seems to cause the problem !!!

Q - Is there a work around or software patch for this problem ??

Any assistance in this regard will be greatly appreciated - Regards Craig Kerr

Current Software is Solid Works 2010 SP4 and Solid Works Task Scheduler 2010 SP4

Operaring system software Window 7

SolidworksTask Scheduler