Fernando,

you haven't mentioned any tools that you are using, or the operating system you use. This makes it a bit difficult to answer your question.

My guess is that you're working with FontLab 4.6.

Also, you haven't mentioned the format that you're generating your OpenType font in -- whether it's OpenType PS aka OpenType-CFF (.otf) or it's OpenType TT/TrueType (.ttf).

If you're using FontLab to generate an OpenType PS font, the Type 1 hinting is automatically converted to CFF hinting. Both hinting systems are very similar, and the conversion is done by Adobe's high-quality FDK for OpenType code that is built into FontLab.

If you're using FontLab to generate an OpenType TT font, the Type 1 hinting is coverted into TrueType hinting instructions. This is a process done by a very advanced TrueType autohinting system developed by the FontLab team. You can control how this conversion is done using Preferences / TrueType / Autohinting Options. You can also do the conversion manually, by using the various actions from Tools / Transform Range.

Regards,
Adam Twardoch
Fontlab Ltd.