[xmonad] xmobar-0.9.1 cannot compile

[Chengqi(Lars) Song]

hi,

this is the output:

	 Configuring xmobar-0.9...
	 Warning: This package indirectly depends on multiple versions of the same
	 package. This is highly likely to cause a compile failure.
	 package X11-xft-0.3 requires utf8-string-0.3.3
	 package xmobar-0.9 requires utf8-string-0.3.4
	 Preprocessing executables for xmobar-0.9...
	 Building xmobar-0.9...
	 Linking dist/build/xmobar/xmobar ...
	 /usr/bin/ld: cannot find -lHSutf8-string-0.3.3

different version of utf8-string are required. how to fix it?

regards
lars