are there custom capabilities for store settings tabs?

hello there

i have some users on my website that can manage the marketpress products. they have typically an editor role. but those users should also be able to edit the coupons. i manage the roles through a plugin and i could give those users a "manage_options" capability. but then they could also edit the wordpress settings, which isn't that cool. and i didn't see any custom capabilities defined by marketpress or didn't i look closely enough?

so, it would be very nice to have some custom capabilities for every settings tab. is this an existing or planned feature? or how could i accomplish my task with the current plugin version?

thanks for the help