grobian@gentoo.org:
Darwin: fix for finding bundles (libtool modules, no equivalent in ELF)
This patch is not really upstreamable, bundles can have any name, but
Apple suggests using .bundle.  libtool on Gentoo generates .bundle files
for modules on Darwin, so we need aspell to actually look for .bundle,
not .so.

--- a/lib/new_filter.cpp
+++ b/lib/new_filter.cpp
@@ -458,11 +458,23 @@
       module->file.assign(option_file.str(), slash + 1 - option_file.str());
       //module->file += "lib";
       module->file += filter_name;
-      module->file += "-filter.so";
+      module->file += "-filter."
+#ifdef __APPLE_CC__
+		  "bundle"
+#else
+		  "so"
+#endif
+		  ;
     } else {
       if (module->file[0] != '/')
         module->file.insert(0, option_file.str(), slash + 1 - option_file.str());
-      module->file += ".so";
+      module->file += "."
+#ifdef __APPLE_CC__
+		  "bundle"
+#else
+		  "so"
+#endif
+		  ;
     }
 
     return module.release();