alter varchar() column length?

Is there a way to alter a varchar column's length? Maybe something like
"alter table foo alter column xyz varchar(256)".

My alternative seems very messy...

- alter table, add a new column with the desired varchar
length. call it "temp"

- insert into "temp" the value of the old column.

- alter table, drop the old column (messing up all the indexes
on that column in the process I suppose)

- alter table, add a new column with the same name as the one
you just deleted, only with the desired length

- insert into that new column the value in "temp"

- alter table, drop "temp"

- recreate all the indexes

Thanks

-dave