Pop punkers SUM 41 have been offered the opening slot on the upcoming IRON MAIDEN world tour."IRON MAIDEN have contacted us and they want us on their world tour next year," SUM 41 bassist Cone "Jay" McCaslin told Sweden's Close-Up magazine. "It turns out that they're big SUM 41 fans." "We fell off our chairs," McCaslin said of the group's reaction to the surprise invitation. "We're pretty much all booked [through the end of next year], but we have to do at least part of the tour. The audience will probably throw beer and shit on us, but we don't care." SUM 41 have made no bones about their appreciation for all things metal and have gone as far to invite SLAYER guitarist Kerry King to guest in a video for "What We're All About", a remixed version of the track that originally appeared on the group's "Half Hour Of Power" CD. Earlier this month, SUM 41 asked reunited Bay Area thrashers EXODUS to join them on the bill at San Francisco's Bottom of the Hill, where the two bands performed in front of a sold-out, 350-capacity crowd.