You need to get the "TermName" like this...
def importPackageOrModuleOrClass(sym: Symbol): Import =
if (sym.isPackage || sym.isModule)
gen.mkWildcardImport(sym)
else
gen.mkImport(sym.enclosingPackage, sym.name.toTermName, sym.name.toTermName)
You can grab more hints regarding importing, reflecting, etc. via the sourcecode at http://xuwei-k.github.io/scala-compiler-sxr/scala-compiler-2.10.0/scala/reflect/internal/Importers.scala.html