Modifying a language file

Hi, I'm using the spanish (sp) language pack. I modified the modules_register.mo in modules->register->locale->es->LC_MESSAGES since there is a small issue with the Register as a new user sentence. I made the correction and then the first time I show the registering page after restarting the apache server I have the following:

Registrar como Nuevo Usuarioish fi_FI.ISO-8859-1 fran?s fr_FR.ISO-8859-1 french fr_FR.ISO-8859-1 galego gl_ES.ISO-8859-1 galician gl_ES.ISO-8859-1 german de_DE.ISO-8859-1 greek el_GR.ISO-8859-7 hebrew he_IL.ISO-8859-8 hrvatski hr_HR.ISO-8859-2 hungarian hu_HU.ISO-8859-2 icelandic is_IS.ISO-8859-1 italian it_IT.ISO-8859-1 japanese ja_JP.eucJP japanese.euc ja_JP.eucJP ja_JP ja_JP.eucJP ja_JP.ujis ja_JP.eucJP japanese.sjis ja_JP.SJIS korean ko_KR.eucKR korean.euc ko_KR.eucKR ko_KR ko_KR.eucKR lithuanian lt_LT.ISO-8859-13 no_NO nb_NO.ISO-8859-1 no_NO.ISO-8859-1 nb_NO.ISO-8859-1 norwegian nb_NO.ISO-8859-1 nynorsk nn_NO.ISO-8859-1 polish pl_PL.ISO-8859-2 portuguese pt_PT.ISO-8859-1 romanian ro_RO.ISO-8859-2 russian ru_RU.ISO-8859-5 slovak sk_SK.ISO-8859-2 slovene sl_SI.ISO-8859-2 slovenian sl_SI.ISO-8859-2 spanish es_ES.ISO-8859-1 swedish sv_SE.ISO-8859-1 thai th_TH.TIS-620 turkish tr_TR.ISO-8859-9

If I go out and then follow the register link I have ...

Registrar como Nuevo Usuario

... as expected. Any advice?. Is there any special way to modify these files?. Thank you.

PS: I'm using Gallery 2.2.4 Developer.

Arunas