[Maybe is the wrong component.] Assuming this might be related to Cairo, since
the same applet works fine with FC4, where the same FreeType version is used.
Else the new GTK+ 2.7.0 or Pango. Full backtrace in separate attachment.

(gdb) bt
#0  0x005076db in memset () from /lib/libc.so.6
#1  0x00768927 in gray_raster_render () from /usr/lib/libfreetype.so.6
#2  0x00767481 in ps_hints_apply () from /usr/lib/libfreetype.so.6
#3  0x00768045 in gray_raster_render () from /usr/lib/libfreetype.so.6
#4  0x00735ca4 in FT_Outline_Render () from /usr/lib/libfreetype.so.6
#5  0x00735d65 in FT_Outline_Get_Bitmap () from /usr/lib/libfreetype.so.6
#6  0x009b9dac in _cairo_output_stream_create_for_file ()
   from /usr/lib/libcairo.so.1
#7  0x009ab86b in cairo_scaled_font_glyph_extents ()
   from /usr/lib/libcairo.so.1
#8  0x009aa1d8 in _cairo_arc_path_negative () from /usr/lib/libcairo.so.1
#9  0x009ba68a in cairo_ft_scaled_font_unlock_face ()
   from /usr/lib/libcairo.so.1
#10 0x009ab161 in cairo_scaled_font_create () from /usr/lib/libcairo.so.1
#11 0x009ab60d in cairo_scaled_font_glyph_extents ()
   from /usr/lib/libcairo.so.1
#12 0x0021ab70 in pango_cairo_fc_font_get_type ()
   from /usr/lib/libpangocairo-1.0.so.0
#13 0x00973335 in pango_font_get_glyph_extents ()
   from /usr/lib/libpango-1.0.so.0
#14 0x001e7dbc in ?? () from /usr/lib/pango/1.4.0/modules/pango-basic-fc.so
#15 0x001e801c in ?? () from /usr/lib/pango/1.4.0/modules/pango-basic-fc.so
#16 0x00979ff7 in _pango_engine_shape_shape () from /usr/lib/libpango-1.0.so.0
#17 0x00988d7d in pango_shape () from /usr/lib/libpango-1.0.so.0
#18 0x0097d61e in pango_layout_set_width () from /usr/lib/libpango-1.0.so.0
#19 0x0097fad2 in pango_layout_iter_get_char_extents ()
   from /usr/lib/libpango-1.0.so.0
#20 0x0098033a in pango_layout_iter_get_char_extents ()
   from /usr/lib/libpango-1.0.so.0
#21 0x009821ed in pango_layout_get_lines () from /usr/lib/libpango-1.0.so.0
#22 0x00b403e7 in gtk_entry_get_text () from /usr/lib/libgtk-x11-2.0.so.0
#23 0x00b4185b in gtk_entry_get_text () from /usr/lib/libgtk-x11-2.0.so.0
#24 0x008b9017 in g_cclosure_marshal_VOID__VOID ()
   from /usr/lib/libgobject-2.0.so.0
#25 0x008abf8b in g_cclosure_new_swap () from /usr/lib/libgobject-2.0.so.0
#26 0x008ac475 in g_closure_invoke () from /usr/lib/libgobject-2.0.so.0
#27 0x008bbdcb in g_signal_stop_emission () from /usr/lib/libgobject-2.0.so.0
#28 0x008bdbc8 in g_signal_emit_valist () from /usr/lib/libgobject-2.0.so.0
#29 0x008bdf19 in g_signal_emit () from /usr/lib/libgobject-2.0.so.0
#30 0x00cb65e8 in gtk_widget_realize () from /usr/lib/libgtk-x11-2.0.so.0
-snip-


Version-Release number of selected component (if applicable):
cairo-0.5.1-3


How reproducible:
always

Steps to Reproduce:
1. build http://home.arcor.de/ms2002sep/tmp/gai-temp-0.1.0-1.src.rpm
   with build dependencies from Fedora Extras
2. add applet to panel (or start it)
3. open "Preferences" dialog, then "choose font" dialog


Actual results: segfault with FC Devel, no crash with FC4


Expected results: no crash