Is There A Alter Table Xxxx Drop Default Yyy ?

Hi:
I need to change a column's datatype from tinyint to int as follows:
alter table tableName
alter column column1 int

but with error <<'DF__LandMarks__color__6A50C1DA' is depending on it.>>

However, this old default is not part of the constraint. Thus, the only way is to delete it from sysobjects.

unfortunately, the following code I have to commented since they could only be executed line by line, not within a begin...end block.
--exec master.dbo.sp_configure 'allow updates', 1
--reconfigure with override
--delete from sysobjects
-- where name = 'DF__LandMarks__color__6A50C1DA'
-- and type = 'D'
--exec master.dbo.sp_configure 'allow updates', 0
--reconfigure with override

I need to update 10 server around 2500 databases with this change.
I have looked INFORMATION_SCHEMA related views, but not found default related, maybe I missed something.

thanks
David