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
if account.currency_id and 'amount_currency' not in vals and account.currency_id.id != account.company_id.currency_id.id:
                vals['currency_id'] = account.currency_id.id
                ctx = {}
                if 'date' in vals:
                    ctx['date'] = vals['date']
                vals['amount_currency'] = account.company_id.currency_id.with_context(ctx).compute(amount, account.currency_id)
        if not ok:
            raise UserError(_('You cannot use this general account in this journal, check the tab \'Entry Controls\' on the related journal.'))
        
        tax_lines_vals = []
        if apply_taxes and not context.get('dont_create_taxes') and vals.get('tax_ids'):
            
            tax_ids = [tax['id'] for tax in self.resolve_2many_commands('tax_ids', vals['tax_ids']) if tax.get('id')]
            
            taxes = self.env['account.tax'].browse(tax_ids)
            currency = self.env['res.currency'].browse(vals.get('currency_id'))
            partner = self.env['res.partner'].browse(vals.get('partner_id'))
            res = taxes.with_context(round=True).compute_all(amount,
                currency, 1, vals.get('product_id'), partner)
            
            if abs(res['total_excluded']) < abs(amount):
                if vals['debit'] != 0.0: vals['debit'] = res['total_excluded']
                if vals['credit'] != 0.0: vals['credit'] = -res['total_excluded']
                if vals.get('amount_currency'):
                    vals['amount_currency'] = self.env['res.currency'].browse(vals['currency_id']).round(vals['amount_currency'] * (res['total_excluded']/amount))
            
            for tax_vals in res['taxes']:
                if tax_vals['amount']: