BizTalk 2004 - ampersand in flat file problem

A colleague of mine is at his wits end trying to solve the following BizTalk problem:

We receive a "|" delimited flat file, for example containing

12345|Some data|SILVER & BLUE|more data|

  This is picked up by an FTP receive port, which then goes through a receive pipeline with just the "flat file disassembler" in it (i.e. nothing in the "Decode", "Validate" or "ResolveParty" stages), before it gets in to an orchestration.

  This works fine most of the time - but in the example above with an ampersand in it, it appears that the flat file dissassembler is trying to parse the flat file as if it were XML. The orchestration is suspended, and in the event log I get the message below - which I read as it saying that it is trying to parse the ampersand as the start of an entity (e.g. "&" or ">") and failed (as "& BLUE|more data|" has neither a terminating ";" nor is a defined entity in the context)

  If I edit the source file and change the "&" to "x" for example, it is processed without error.

  Any ideas whether it is possible to tell BizTalk that the flat file is just plain ASCII, it must not be parsed as if it contains XML entities (which I'd have expected to be the default for an flat file)

Any comments or suggestions on solving this are greatly appreciated.

Thanks!