Why not just setup a translate table as Jens suggested. All it takes is an INI file as follows:

GW.INI
code:
[GATEWAY]
172.22.13.251=172.22.13.252

Then a bit of code as follows will do the trick:
code:
break on
$RC=ReadProfileString("C:\KiX4.02\GW.INI","GATEWAY","172.22.13.251")
$RC ?
Get $_

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