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)

""" Function overwritten in account_tax_exigible to make sure we consider only the lines having tax_exigible set to False """
        return False
    def _get_tax_cash_basis_lines(self, value_before_reconciliation):
        
        tax_group = {}
        total_by_cash_basis_account = {}
        line_to_create = []
        move_date = self.debit_move_id.date
        for move in (self.debit_move_id.move_id, self.credit_move_id.move_id):
            if move_date < move.date:
                move_date = move.date
            for line in move.line_ids:
                
                
                
                matched_percentage = value_before_reconciliation[move.id]
                amount = (line.credit_cash_basis - line.debit_cash_basis) - (line.credit - line.debit) * matched_percentage
                if not self._check_tax_exigible(line):
                    if line.tax_line_id and line.tax_line_id.use_cash_basis:
                        
                        acc = line.account_id.id
                        if tax_group.get(acc, False):
                            tax_group[acc] += amount
                        else:
                            tax_group[acc] = amount
                        
                        acc = line.tax_line_id.cash_basis_account.id
                        key = (acc, line.tax_line_id.id)
                        if key in total_by_cash_basis_account: