Preheat a grill to medium-high. in a food processor, combine the butter, lime zest and juice, jalapeno, honey and 1/2 tsp. salt. process, scraping down the sides of the bowl, until the jalapeno is finely chopped, about 30 seconds.
Spread some butter on the cut sides of the bread. grill, cut sides down, until toasted, 3 to 5 minutes. Serve the leftover butter for slathering on the corn from the crab boil, or melt it and serve it with the crabs for dipping.