Usage of Text Symbols in Select Querys and Work Flow

[Kesari Katakam]

Hi All,

We had a typical problem, in a function module , a developer has used
text symbols instead of  constants.

These things worked in Development and Quality systems when the work
flow is executed.

But the work flow failed in Production. 
Even though the FM , and the BAPI were executing separately in the
production system, when the work flow is executed, the select query
failed.

Can any body explain this behaviour..!?

(We have changed the text symbols to constants , then the work flow
worked fine )

Thanks and regards
Kesari.