Configuration:
- Company Currency: MXN
- Tax 16%.
- Multicurrency, MXN and USD.
- Decimal precision: 4
- Currency Data:
MXN: rate 1.0
USD rates

| Database time | rate | Local time (Mexico) | 
| --- | --- | --- |
| 2016-09-09 00:00:01 | 0.054440 | 2016-09-08 17:00:01 |
| 2016-10-11 00:00:01 | 0.051815 | 2016-10-10 17:00:01 |

Steps to reproduce:

1. Create an invoice for 600 USD  + tax (16%) with date 09/09/16 (September 9, 2016) and when you validate in the journal entry is $12,784.7172 MXN.
3. Create a bank statement in MXN and add a line with date 11/10/16 (October 11, 2016) and amount $13,372.80 MXN.
4. When reconcile select the invoice and there is a difference ($588.0828 MXN) add a line with the difference and select an account for the difference. 
<img width="607" alt="captura de pantalla 2016-11-04 a la s 17 23 26" src="https://cloud.githubusercontent.com/assets/6758279/20025385/749605a2-a2b3-11e6-8b1a-4e9fbf1521ed.png">

**Note that the amount of difference is $588.08 in when you select the account**

5. Click on reconcile.

Expected behavior:
- Reconcile the invoice and create account move.

Current behavior:
- Raise an error  `Wrong credit or debit value in accounting entry !`

![captura de pantalla 2016-11-01 a la s 19 18 52](https://cloud.githubusercontent.com/assets/6758279/19913537/1c272866-a069-11e6-9b06-5851681c7fa5.png)

addons/account/models/account_move.py
company_ids = set()
        all_accounts = []
        partners = set()
        for line in self:
            company_ids.add(line.company_id.id)
            all_accounts.append(line.account_id)
            if (line.account_id.internal_type in ('receivable', 'payable')):
                partners.add(line.partner_id.id)
            if line.reconciled:
                raise UserError(_('You are trying to reconcile some entries that are already reconciled!'))
        if len(company_ids) > 1:
            raise UserError(_('To reconcile the entries company should be the same for all entries!'))
        if len(set(all_accounts)) > 1:
            raise UserError(_('Entries are not of the same account!'))
        if not all_accounts[0].reconcile:
            raise UserError(_('The account %s (%s) is not marked as reconciliable !') % (all_accounts[0].name, all_accounts[0].code))
        if len(partners) > 1:
            raise UserError(_('The partner has to be the same on all lines for receivable and payable accounts!'))
        
        remaining_moves = self.auto_reconcile_lines()
        
        if writeoff_acc_id and writeoff_journal_id and remaining_moves:
            all_aml_share_same_currency = all([x.currency_id == self[0].currency_id for x in self])
            writeoff_vals = {
                'account_id': writeoff_acc_id.id,
                'journal_id': writeoff_journal_id.id
            }