activerecord + ms sql.. rowguid field for merge replication breaking inserts

i got my app running with ms sql server as the database and everything
worked fine. migrations, indexes, constraints, find, create, update,
etc.. the app isn't actually a web app, butwill be running isolated on
severally diff machines that may not have consistent internet access..
part of the requirements was to setup replication so that eventually
the separate instances would 'phone home' and replicate their data on
our main sql server database.

runnign the replication wizard changed my tables by adding a 'rowguid'
column and now activerecord breaks with the following error when i try
to create a new record:

[unixODBC][FreeTDS][SQL Server]Conversion failed when converting from
a character string to uniqueidentifier.: INSERT INTO [companies]
([created_at], [name], [updated_at], [rowguid]) VALUES('2010-06-25
20:23:06.032', 'test', '2010-06-25 20:23:06.032', 'newsequentialid(')

what are my alternatives to get this to work again?