use the bit varying(n)

Hello,

when I learn how to use the varbit(n) datatype, I got the error:

test=# create table testdt ( b varbit(2) );
ERROR: parser: parse error at or near "("

but can use as below :
test=# create table testdt ( b bit varying(2) );
CREATE

The version is:
test=# select version();
version
-------------------------------------------------------------
PostgreSQL 7.2.3 on i686-pc-linux-gnu, compiled by GCC 2.96

Let's make things better!
RongCS(容创森)
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