Moving this from a downstream bug report:
https://bugzilla.redhat.com/show_bug.cgi?id=722837

Description of problem:
while writing a mail with HTML format, there was error on terminal, showing
above error: "gtkhtml-editor-WARNING  :zh-CN: No such language

Version-Release number of selected component (if applicable):
evolution-3.0.1-1.fc15.i686
gtkhtml3-4.0.1-1.fc15.i686

How reproducible:
everytime

Steps to Reproduce:
1. run evolution with locale zh_CN from terminal
2. create new mail with HTML format
3. type something with ibus zh_CN locale
4. check terminal

Actual results:
there is above said error on terminal

Expected results:
no such error should exist

------------------------------------------------------------------

Actually this error throws in gnome-terminal, when choose HTML format for all
the Indic, CJK and EMEA Locales. We generally write locale name as like ja_JP,
or it_IT, or pt_BR, or bn_IN, or pa_IN. But here in the error message, it using
dash (-), instead of underscore (_). Although devel can say the exact reason
behind this.

------------------------------------------------------------------

The Warnings for various locales thrown in G-T :

[smaitra@localhost ~]$ evolution &
[6] 13961
[5]   죽었음               evolution
[smaitra@localhost ~]$ 
(evolution:13961): gtkhtml-editor-WARNING **: ko-KR: No such language

[6]+  Done                    evolution

[smaitra@localhost ~]$ evolution &
[4] 14159
[smaitra@localhost ~]$ 
(evolution:14159): gtkhtml-editor-WARNING **: it-IT: No such language

[4]+  Done                    evolution

[smaitra@localhost ~]$ evolution &
[4] 14299
[smaitra@localhost ~]$ 
(evolution:14299): gtkhtml-editor-WARNING **: bn-IN: No such language

(gedit:13300): IBUS-WARNING **: _connection_closed_cb: Underlying GIOStream
returned 0 bytes on an async read

(firefox:13448): IBUS-WARNING **: _connection_closed_cb: Underlying GIOStream
returned 0 bytes on an async read

(evolution:14299): IBUS-WARNING **: _connection_closed_cb: Underlying GIOStream
returned 0 bytes on an async read

[smaitra@localhost ~]$ evolution

(evolution:13672): GLib-GObject-WARNING **: g_object_get_property: object class
`EShellSettings' has no property named `cal-primary-calendar'

(evolution:13672): GLib-GObject-WARNING **: g_object_set_property: object class
`EShellSettings' has no property named `cal-primary-calendar'

(evolution:13672): gtkhtml-editor-WARNING **: ja-JP: No such language