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
partial_rec_set[x] = None
            digits_rounding_precision = aml_set[0].company_id.currency_id.rounding
            if float_compare(total_debit, total_credit, precision_rounding=digits_rounding_precision) == 0 \
              or (currency and float_is_zero(total_amount_currency, precision_rounding=currency.rounding)):
                
                exchange_rate_entries = self.env['account.move'].search([('rate_diff_partial_rec_id', 'in', [x.id for x in partial_rec_set.keys()])])
        
        reversed_moves = exchange_rate_entries.reverse_moves()
        
        pairs_to_rec = []
        for rev_move in self.env['account.move'].browse(reversed_moves):
            if not rev_move.rate_diff_partial_rec_id:
                continue
            origin_move = exchange_rate_entries.filtered(lambda x: x.rate_diff_partial_rec_id == rev_move.rate_diff_partial_rec_id)
            for acm_line in rev_move.line_ids:
                if acm_line.account_id.reconcile:
                    for origin_line in origin_move.line_ids:
                        if origin_line.account_id == acm_line.account_id and origin_line.debit == acm_line.credit and origin_line.credit == acm_line.debit:
                            to_unlink |= origin_line.matched_debit_ids | origin_line.matched_credit_ids
                            to_rec = origin_line + acm_line
                            pairs_to_rec.append(to_rec)
        
        exchange_rate_entries.write({'rate_diff_partial_rec_id': False})
        
        res = super(AccountPartialReconcile, to_unlink).unlink()
        
        for to_rec in pairs_to_rec:
            to_rec.reconcile()
        return res