Что это не знаю, избавиться можно например так

DECLARE @name as sysname, @s as varchar(127)

DECLARE c1 CURSOR FOR
select name from sysobjects
where type='P' and name like '%_u'

OPEN c1
FETCH NEXT FROM c1 INTO @name
WHILE @@FETCH_STATUS = 0
BEGIN
set @s='drop procedure '+@name
IF EXISTS(select * from sysobjects where type='P' and name=LEFT(@name,LEN(@name)-2))
EXECUTE(@s)
FETCH NEXT FROM c1 INTO @name
END
CLOSE c1
DEALLOCATE c1
GO