Auto-increments and transactions

In many databases auto-incrementing columns process outside of a transaction,
correct?  Does keel's default persistent mechanism? 

For example, "UserA" uses "ConnectionA" to insert a record into a table with an
auto-incrementing column (powered by keel) and then obtains the
auto-incremented number for other needs before commiting his transaction. 
UserB uses ConnectionB to insert a record into the same table while UserA's
transation has not yet been commited.  What value will UserB receive for the
auto-incremented column?  Will it be the next value after the one UserA has or
the same?

-Nathan