On Windows Vista and Windows 7 (XP and Ubuntu seem ok):

If the system locale is used (using locale.setlocale(LC_ALL, '') and the system locale is set to dutch belgium: 
If the regional options are set to format negative monetary items as "<EURO sign> -<value>", than locale.currency(value) will format it as "<EURO sign)value-".

Other formatting options works ok: e.g. if the regional settings display negative monetary items as "(value)", than "locale.currency(value)" will also display "{value)".

Reproducable on Python 2.6.x, 2.7.x and 3.1.2 on Windows Vista (32 bit)

I don't have a copy of Vista or 7 handy to check with. Could you tell me what locale.localeconv() returns on a non-working system and on a working system (preferably Windows XP)?

*  On Windows Vista (non working system): 

>>> locale.localeconv()
{'mon_decimal_point': ',', 'int_frac_digits': 2, 'p_sep_by_space': 1, 'frac_digits': 2, 'thousands_sep': '.', 'n_sign_posn': 4, 'decimal_point': ',', 'int_curr_symbol': 'EUR', 'n_cs_precedes': 1, 'p_sign_posn': 4, 'mon_thousands_sep': '.', 'negative_sign': '-', 'currency_symbol': '\x80', 'n_sep_by_space': 1, 'mon_grouping': [3, 0], 'p_cs_precedes': 1, 'positive_sign': '', 'grouping': [3, 0]}


* On Windows XP (Working system):
{'mon_decimal_point': ',', 'int_frac_digits': 2, 'p_sep_by_space': 1, 'frac_digits': 2, 'thousands_sep': '.', 'n_sign_posn': 1, 'decimal_point': ',', 'int_curr_symbol': 'EUR', 'n_cs_precedes': 0, 'p_sign_posn': 1, 'mon_thousands_sep': '.', 'negative_sign': '-', 'currency_symbol': '\x80', 'n_sep_by_space': 1, 'mon_grouping': [3, 0], 'p_cs_precedes': 0, 'positive_sign': '', 'grouping': [3, 0]}

The locale is set to 'Dutch_Belgium.1252'

So it looks like locale.currency() is doing the right thing, given the values returned by locale.localeconv().

These values are copied from C's localeconv(), so the problem must be there. I don't see how we can do anything about it on the Python side, unfortunately.