Getting values from fixed value in domain

Hi,

There is one field called company code. for this field if the user select the value from drop down box(F4 help), then it should display the corresponding text. the thing is, the values are getting from fixed value which is defined in domain, and it is not in value table or text table. so how i can get this correponding text value for the selected value? Is there any options?

Please help me it urgent...

Regards,

Amal