I get this when I try to build tomboy with jhbuild on Fedora development:

gmcs -debug -target:exe -out:Tomboy.exe -debug -define:DEBUG -unsafe -target:exe -define:ENABLE_DBUS  -d:GTK_2_10 Tomboy.cs Search.cs AbstractAddin.cs ActionManager.cs AddinManager.cs AddinPreferenceFactory.cs Applet.cs ApplicationAddin.cs Logger.cs Note.cs NoteAddin.cs NoteEditor.cs NoteManager.cs NoteWindow.cs NoteBuffer.cs NoteTag.cs Preferences.cs PreferencesDialog.cs PreferenceTabAddin.cs RecentChanges.cs Tag.cs TagButton.cs TagManager.cs TagEntry.cs Tray.cs Trie.cs Undo.cs Utils.cs Watchers.cs WrapBox.cs XKeybinder.cs Notebooks/CreateNotebookDialog.cs Notebooks/NotebookApplicationAddin.cs Notebooks/Notebook.cs Notebooks/NotebookManager.cs Notebooks/NotebookMenuItem.cs Notebooks/NotebookNewNoteMenuItem.cs Notebooks/NotebookNoteAddin.cs Notebooks/NotebooksTreeView.cs Synchronization/FileSystemSyncServer.cs Synchronization/FuseSyncServiceAddin.cs Synchronization/SyncDialog.cs Synchronization/SyncManager.cs Synchronization/SyncServiceAddin.cs Synchronization/SyncUtils.cs Synchronization/TomboySyncClient.cs panelapplet/BonoboUIVerb.cs panelapplet/ChangeBackgroundHandler.cs panelapplet/ChangeSizeHandler.cs panelapplet/GnomeSharp.PanelAppletFactoryCallbackNative.cs panelapplet/MoveFocusOutOfAppletHandler.cs panelapplet/ObjectManager.cs panelapplet/PanelAppletBackgroundType.cs panelapplet/PanelApplet.cs panelapplet/PanelAppletFactoryCallback.cs panelapplet/PanelAppletFactory.cs panelapplet/PanelAppletFlags.cs Gnome.Keyring/AccessRights.cs Gnome.Keyring/AttributeType.cs Gnome.Keyring/GenericItemData.cs Gnome.Keyring/ItemACL.cs Gnome.Keyring/ItemData.cs Gnome.Keyring/ItemType.cs Gnome.Keyring/KeyringException.cs Gnome.Keyring/KeyringInfo.cs Gnome.Keyring/NetItemData.cs Gnome.Keyring/NoteItemData.cs Gnome.Keyring/Operation.cs Gnome.Keyring/RequestMessage.cs Gnome.Keyring/ResponseMessage.cs Gnome.Keyring/ResultCode.cs Gnome.Keyring/Ring.cs RemoteControl.cs RemoteControlProxy.cs Defines.cs -r:/opt/gnome2/lib/pkgconfig/../../lib/mono/gtk-sharp-2.0/pango-sharp.dll -r:/opt/gnome2/lib/pkgconfig/../../lib/mono/gtk-sharp-2.0/atk-sharp.dll -r:/opt/gnome2/lib/pkgconfig/../../lib/mono/gtk-sharp-2.0/gdk-sharp.dll -r:/opt/gnome2/lib/pkgconfig/../../lib/mono/gtk-sharp-2.0/gtk-sharp.dll -r:/opt/gnome2/lib/pkgconfig/../../lib/mono/gtk-sharp-2.0/glib-sharp.dll -r:/opt/gnome2/lib/pkgconfig/../../lib/mono/gtk-sharp-2.0/art-sharp.dll -r:/opt/gnome2/lib/pkgconfig/../../lib/mono/gtk-sharp-2.0/gnome-vfs-sharp.dll -r:/opt/gnome2/lib/pkgconfig/../../lib/mono/gtk-sharp-2.0/gconf-sharp.dll -r:/usr/lib/mono/gtk-sharp-2.0/gnome-sharp.dll   -r:Mono.Posix -r:/usr/lib/mono/ndesk-dbus-1.0/NDesk.DBus.dll -r:/usr/lib/mono/ndesk-dbus-glib-1.0/NDesk.DBus.GLib.dll   -r:../Mono.Addins/Mono.Addins/Mono.Addins.dll -r:../Mono.Addins/Mono.Addins.Setup/Mono.Addins.Setup.dll -r:../Mono.Addins/Mono.Addins.Gui/Mono.Addins.Gui.dll -resource:../data/GNOME_TomboyApplet.xml,GNOME_TomboyApplet.xml -resource:../data/UIManagerLayout.xml -resource:../data/icons/hicolor_apps_48x48_tomboy.png,tomboy.png -resource:../data/icons/hicolor_places_22x22_note.png,note.png -resource:../data/icons/hicolor_actions_16x16_note-new.png,note-new.png -resource:../data/icons/hicolor_actions_22x22_filter-note-all.png,filter-note-all.png -resource:../data/icons/hicolor_actions_22x22_filter-note-unfiled.png,filter-note-unfiled.png -resource:../data/icons/hicolor_places_22x22_notebook.png,notebook.png -resource:../data/icons/hicolor_actions_48x48_notebook-new.png,notebook-new.png -resource:../data/icons/hicolor_status_16x16_pin-down.png,pin-down.png -resource:../data/icons/hicolor_status_16x16_pin-up.png,pin-up.png -resource:../data/icons/hicolor_status_16x16_pin-active.png,pin-active.png -resource:./Tomboy.addin.xml
Synchronization/FuseSyncServiceAddin.cs(130,41): warning CS0642: Possible mistaken empty statement
Synchronization/FuseSyncServiceAddin.cs(133,49): warning CS0642: Possible mistaken empty statement
NoteWindow.cs(17,21): warning CS0612: `Gtk.Tooltips' is obsolete
NoteTag.cs(455,40): warning CS0108: `Tomboy.DepthNoteTag.Direction' hides inherited member `Gtk.TextTag.Direction'. Use the new keyword if hiding was intended
/opt/gnome2/lib/mono/gac/gtk-sharp/2.12.0.0__35e10195dab3c99f/gtk-sharp.dll (Location of the symbol related to previous warning)
PreferencesDialog.cs(5,13): error CS0234: The type or namespace name `PropertyEditors' does not exist in the namespace `GConf'. Are you missing an assembly reference?
PreferencesDialog.cs(5,1): error CS0246: The type or namespace name `GConf.PropertyEditors' could not be found. Are you missing a using directive or an assembly reference?
PreferencesDialog.cs(799,43): error CS0246: The type or namespace name `PropertyEditor' could not be found. Are you missing a using directive or an assembly reference?
Tray.cs(126,21): warning CS0612: `Gtk.Tooltips' is obsolete
WrapBox.cs(103,29): warning CS0108: `Tomboy.WrapBox.Remove(Gtk.Widget)' hides inherited member `Gtk.Container.Remove(Gtk.Widget)'. Use the new keyword if hiding was intended
/opt/gnome2/lib/mono/gac/gtk-sharp/2.12.0.0__35e10195dab3c99f/gtk-sharp.dll (Location of the symbol related to previous warning)
PreferencesDialog.cs(5,13): error CS0234: The type or namespace name `PropertyEditors' does not exist in the namespace `GConf'. Are you missing an assembly reference?
PreferencesDialog.cs(5,1): error CS0246: The type or namespace name `GConf.PropertyEditors' could not be found. Are you missing a using directive or an assembly reference?
Compilation failed: 5 error(s), 6 warnings
make[3]: *** [Tomboy.exe] Error 1
make[3]: Leaving directory `/home/kmaraas/cvs/gnome/tomboy/Tomboy'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/home/kmaraas/cvs/gnome/tomboy/Tomboy'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/kmaraas/cvs/gnome/tomboy'
make: *** [all] Error 2
*** error during stage build of tomboy: ########## Error running make   *** [18/39]