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)

company_currency = self[0].account_id.company_id.currency_id
        writeoff_currency = self[0].currency_id or company_currency
        if not self._context.get('skip_full_reconcile_check') == 'amount_currency_excluded' and 'amount_currency' not in vals and writeoff_currency != company_currency:
            vals['currency_id'] = writeoff_currency.id
            sign = 1 if vals['debit'] > 0 else -1
            vals['amount_currency'] = sign * abs(sum([r.amount_residual_currency for r in self]))
        
        first_line_dict = vals.copy()
        first_line_dict['account_id'] = self[0].account_id.id
        if 'analytic_account_id' in first_line_dict:
            del first_line_dict['analytic_account_id']
        if 'tax_ids' in first_line_dict:
            del first_line_dict['tax_ids']
        
        second_line_dict = vals.copy()
        second_line_dict['debit'], second_line_dict['credit'] = second_line_dict['credit'], second_line_dict['debit']
        if 'amount_currency' in vals:
            second_line_dict['amount_currency'] = -second_line_dict['amount_currency']
        
        writeoff_move = self.env['account.move'].create({
            'journal_id': vals['journal_id'],
            'date': vals['date'],
            'state': 'draft',
            'line_ids': [(0, 0, first_line_dict), (0, 0, second_line_dict)],
        })
        writeoff_move.post()
        
        return writeoff_move.line_ids.filtered(lambda r: r.account_id == self[0].account_id)
    @api.model
    def compute_full_after_batch_reconcile(self):