autoconf error on ubuntu 11.04

I know it's a bit late, but you just have to install the library libgtk2.0-dev:

sudo apt-get install libgtk2.0-dev

If you get errors about something related to GLIB, then install libglib2.0-dev as well:

sudo apt-get install libglib2.0-dev

Given the name AM_PATH_GTK_2_0, one makes the following sequence of observations: 1) "AM_" is in automake's namespace, so that m4 macro must come from automake. 2) Hmmm, it isn't in automake. 3) It probably comes from gtk, so the gtk developer's have made an error in naming their m4 macro in conflict with automake. That's a bug in gtk, but I'll probably need to download the newest version of gtk to get the macro.

The problem is that you don't have the m4 macro that gtk expects you to have. You probably need to install libgtk-devel (or something like that). If I am correct and libgtk is indeed installing an m4 macro named AM_..., please report that as a bug to the developers. They are stomping on automakes' namespace (this is, unfortunately, an extremely common error.)

Since you mention downloading automake, I think the problem is that you are running aclocal that is not looking in /usr/share/aclocal, but in a different location (ie, you installed automake in /usr/local) When you installed libgtk-dev, it probably installed the *.m4 file in /usr/share/aclocal, but you need that file in /usr/local/share/aclocal (or $prefix/share/aclocal, where prefix is what you used to install automake.) The simplest solution is to copy that file to $(aclocal --print) That is, run "aclocal --print" to see where aclocal is looking for m4 files, then find the file that libgtk-dev installed that defines the improperly named m4 macro and copy that file to the appropriate location. Alternatively (and probably a better solution) you can put a file named dirlist in $(aclocal --print) that contains the single line "/usr/share/aclocal", so that your hand installed aclocal will always look for m4 files that are installed in /usr/share.