Replicating DDL From Multiple Publishers To One Subscriber

In my situation I have multiple transactional publishers replicating to a single subscriber in SQL2005. When making table changes (like adding a column) I want to be able to add the column to one publisher, let it replicate and then add the column to the remaining publishers and have it not replicate (because it would error trying to add a column that already exists on the subscriber). So I thought I could set the first publisher to "Replicate Schema Changes = True" and the remaining to False. Then add the column to each publisher and then insert new rows in each publisher table. It works for the first publisher, but the remaining publishers fail with "stored procedure sp_MSins_dboMYTABLE expects parameter @c3 which was not supplied". The remaining publishers don't seem to recognize the new column to pass the value the subscriber sproc.

I feel I'm missing something basic here. Is there a way to fix this? Or a better way altogether?

Thanks!