I found this to be extremely annoying bug ("issue" in BB-speak) and would love to know if anyone has any updates/solutions/workarounds:
When a Microsoft® Office 2007 Word attachment is saved in Microsoft Office 2007 or Microsoft Office 97-2003, the attachment will not open on the BlackBerry device. The BlackBerry device will display the following error message: "Unrecognized document format".
This is a previously reported issue that has been escalated internally to our development team. No resolution time frame is currently available.
See the post - BB Support Site Link:
http://www.blackberry.com/btsc/search.do?cmd=displayKC&docType=kc&externalId=KB13 460&sliceId=SAL_Public&dialogID=17761779&stateId=0 %200%2017763077[/url]: BlackBerry Search Results