discount coupon admin error

i have three shops all running latest 1.3.9h, perfectly (it seems).

decided to turn on discount coupon module and use it but i have an error come up when i go to coupon admin:

1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-0, 0' at line 1
in:
[select coupon_id, coupon_code, coupon_amount, coupon_type, coupon_start_date,coupon_expire_date,uses_per_user,uses_per_coupon,restrict_to_products, restrict_to_categories, date_created,date_modified, coupon_active, coupon_zone_restriction from zen_coupons where coupon_active='Y' and coupon_type != 'G' limit -0, 0]
If you were entering information, press the BACK button in your browser and re-check the information you had entered to be sure you left no blank fields.

i've already done a search and not found an answer.

mysql version is 5.1.56

can anyone help me please? what file do i need to change and where is it?

Simple.
Admin->Configuration->Maximum Values
You have blank or zero values there.
There should be no 0 or blank values there, except in the two cases where 0 is presented as a choice or explained in the instructions next to the input box.

thanks, i checked max values but couldn't really find anything that looked like it needed changing.

so i looked at gv coupons and saw max discounts per page was at 0.

changed that to 1 and the error disappears.

maybe you guys can build in a feature so when coupons gets switched on, it automatically defaults to more than 0 in gv coupons?

would be nicer to work without errors when its first switched on...

cheers anyway :~)

The default value for that is 20 on a fresh install. No errors there.

Moved to Bug Reports. To action.