Ian,
The & is probably defined in the MSH-2 field and is the sub-component separator.
So the sending system SHOULD be following the standard and escaping that (the escape character also in MSH-2 is probably ).
There is a standard notation specified in the HL/7 standard for escaping the sub-component character no matter what the actual cahracter is. That notation is T (assuming is the escape character in MSH-2).
Try contacting the source system and ask if they will follow the standard and escape separators appropriately.
Then the receiving system needs to be able to reverse the escaping – or – you can do that with a proc after the Xlate.
If the source system will not or cannot do the escaping for you then there are a lot of mechanisms (non of them as reliable as the escaping mechanism from the source) which can be deployed – including what Steve prorposed (although if you have any REAL sub-component separators in the message those will be lost with that technique).
Even if you were to preserve the invalid sub-component character will the receiving system have similar problems?
email: jim.kosloskey@jim-kosloskey.com 29+ years Cloverleaf, 59 years IT - old fart.
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