Who knew? Certainly not I!
Both early works dating from the composer's mid-teens, they're on cpo.
Review here:
http://www.musicweb-international.com/classrev/2000/dec00/leharSonatas.htm
No, me neither.
I'd say don't bother. Curiosity value only. The longer sonata in D minor is pretty thin stuff dragged out to nearly 40 minutes.
I agree with Alan. I heard this, years ago and actually dozed off in the middle of the CD. It was part of a box set, if I remember correctly - the other orchestral works included a charming small violin concertino and an assortment of unheard waltzed and suites.