it seems that mantis is slotted... Available versions: (1.0.8-r1) 1.0.8-r1 (1.1.1) ~1.1.1 should that be more like Available versions: (1.0) 1.0.8-r1 (1.1) ~1.1.1 because 1.1.2 is part of the 1.1 line and 1.0.8-r1 is part of the 1.0 line. Reproducible: Always
This is no a bug but a feature provided by webapps.eclass. It allows different revisions of same webapp being installed in paralle. Thus you can install and then test any revisions of web-application. If you need details read webapp.eclass documentation and I remember there was an article about webapp-config (I hope google helps you to find it). WONTFIX.