begin/end/abort work for sequences?

I assumed that wrapping a call to nextval() in a transaction would allow
me to roll back the update of the sequence. But when I do the following:

begin;
select nextval('po_seq');
abort;

The sequence po_seq is advancing to the next value even though the
transaction was aborted. If I put other things like updates, inserts, etc.
inside the transaction, they seem to be rolled back OK, but not the
update of the sequence.

Am I doing something wrong?

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Kyle Bateman President, Action Target Inc.
"Viva Yo!" kyle(at)actarg(dot)com (801)377-8033x101
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