You need this document from the Financial Services Authority:
http://www.moneymadeclear.fsa.gov.uk/pdfs/bank _accounts.pdf
In particular, see the last column of the table on page 4, which indicates the categories of people who are unable to get each type of account. You'll see that 'undischarged bankrupt' appears against every account except for these two:
Barclays Cash Card Account
Cooperative Cashminder
So it seems that you ought to try getting one of those two accounts.
I've got a Barclays Cash Card Account and, while I'm not bankrupt, I don't recall any questions about bankruptcy on the application form. If you get the leaflet from a branch of Barclays it will probably only show that you can withdraw cash from ATMs at Barclays Bank or at the Post Office. That's not actually true; the card works in any UK cash machine. Interestingly, that FSA document states that you can get a debit card (rather than just a cash machine card) with the Barclays Cash Card Account. That wasn't the case when I opened my account (several years ago) but it looks like things might have changed for the better.
Hoping this helps,
Chris