Since 30-07-2011 sage's enchants work differently on MOTR.
In particular:
-The weapon cannot be destroyed because of the enchant.
-There is only 1% chance that the elemental sphere will be consumed (or so the administration says)
-The duration of enchant for each of the levels of the skills is 10, 20, 40,70 and 120 seconds respectively, which means it lasts only 2 minutes on lvl 5.
That is so-called "Active enchant". After this update enchants are seldom used in leveling, although it is theoretically possible to use them. But considering that enchanting skills affect the damage of some of the Sorcerer's skills, Scholars still learn those skills.
The converters still work the same way as before (3 minute duration).