[web2py] How to set multiple primary key?

[Iceberg]

Hi there,

I am fiddling multiple primary keys. Somehow I managed to find
following example inside gluon/sql.py

        db.define_table('account',
          Field('accnum','integer'),
          Field('acctype'),
          Field('accdesc'),
          primarykey=['accnum','acctype'])

But running the example throws:

Traceback (most recent call last):
  ......
  File "C:\DOWNLOAD\google_appengine\web2py\gluon\sql.py", line 2112,
in __init__
    raise SyntaxError, 'invalid table "%s" attribute: %s' %
(tablename, k)
SyntaxError: invalid table "account" attribute: sequence_name

What did I do wrong?

Iceberg