And... I've done it!
Yesterday, partly pushed by a friend, I dared to give my first voice class (Sculptcrafter/The basics). Since all my classes have been text, there was no problem to catch up, as everything was also said in text chat, but, wow! I had forgotten how good I feel when I'm giving a RL-class. My spoken English is not exactly perfect, but looks like everybody was able to understand me, which is the important. I promise I'll keep practicing.
I'm so happy for this!
The only bad side for all this is that I can't tell anymore my students that in RL I'm a man :o) (they never believed me, anyway).