When an exclude dependency is declared in the Gradle DSL, this dependency is being incorrectly applied to the module that is the target of the dependency. This regression was introduced as part of the fix for GRADLE-2674.

http://forums.gradle.org/gradle/topics/breaking-change-regarding-exclude-group-between-gradle-1-12-and-2-3-rc2

This issue has been fixed: any exclude that only declares group and/or module will only apply to module dependencies, not to the module artifacts. This behaviour is slightly inconsistent with the way Ivy deals with ivy.xml excludes.