vale, esto es lo que me han contado:
Voice search uses a speech engine and voice data - if you go into settings -> text-to-speech on the desire there is an option to "Install Voice Data". Under the default settings in that same place is a "Language" option - mine has Spanish listed as one of 6 available languages.
Similarly, you should also install TTS Extended (search TTS on the market, should be the first option from Eyes-Free Project), and you can change between the Pico TTS and eSpeak TTS engines. Currently using Pico and in my "Default Language" options there are about 37 languages, of which Spanish is one
Just install the VoiceSearch2.1.apk that's floating around, and if you like also look on XDA (I think in the G1 forums) for the htc_ime_jonasl_hires.zip - it has the latest (my installed version is 2.4) modified HTC keyboard (same as you currently use in Sense, only with the microphone icon so you can dictate into any text box, and plenty more customisable options). DO NOT install the Clicker.apk inside the package - this is not needed for Sense devices.
With all this done you will have Spanish language, Voice TTS in text boxes, voice dialing by holding the search key and saying "llamar a ..." and voice search as well
all without Root.
Although if you're going to root anyway paul has just finished
-Andrew
Just did a quick search for you, here is the Voicesearch 2.1 that you need from Google Code:
http://code.google.com/p/voicesearch/downl...;q=#makechanges
And here is the XDA thread you need to install the modified keyboard:
http://forum.xda-developers.com/showthread.php?t=624416
Probad criaturas y me decis, que yo todavia no tengo desi