Is the saving in .ai problem fixed in CS5?

Question

I am one of hundreds if not thousands of people who could no longer save .ai images in Illustrator after getting automatic Adobe updates in October 2009.
I spent months try to resolve the problem - trying every method suggested by Illustrator professionals on all the Illustrator forums, and none of them worked -reinstalling illustrator, deleting preferences, deinstalling acrobat, shutting down the windows media center etc. One thing I noticed is that most of the people who had the problem either had Sony Vaios (as I have) or Dell Inspirons - and in fact, several people with Sony Vaios said that last fall's automatic updates by Adobe were incompatible with Sony Vaios and responsible for preventing Illustrator from saving in many file formats, notably .ai. What is so frustrating is that I teach Illustrator at several schools, and since I can't save images as .ai files, I have to keep providing files in other formats and working in other formats and explaining to students about the .ai problem on many computers.
ANYWAY I'm about to upgrade to CS5. And I'm about to get a new computer -- another Sony Vaio (but with Windows 7) since I'm totally happy with the computer except in regard to the Illustrator issue and get excellent onsite for the Vaios locally.
****What I'm wondering is that if people who were unable to save illustrator files in .ai format in CS3 or CS4 since the updates last October are able to save it in CS5. *****
Anyone out there who had this issue who is finding it resolved with CS5?
If not, I'm going to have to rethink my teaching and start dropping my Illustrator classes and focus more intensively on Photoshop. Illustrator is an expensive program with a high learning curve, and should be configured so that everyone can save in its native file format.
Tracy in Boston

Answer 1

"What I need to know is exactly what kind problem that was (I would like to be given as many details as possible," etc.
Warning here! I asked Nokia people EXACTLY THIS QUESTION THREE TIMES and THREE TIMES THEY DELETED MY POSTS saying that I was 'disrespectful' to both Nokia itself and its users! What a mess... 'Don't peek your nose into the affair that shouldn't bother you, dude. Go buy a Droid if you like' Was I right tat the deletion of my posts meant exactly that? Well, I've bought a Droid just as you had avised me, guys. Thank you!
PS. Why not to be just honest with your customers? What about corp.openness? What about Siemens once getting out of mobile biz straight after their S65 epic failure that they chose to silence? S65 was turning down by itself when squeezed in owner's hand due to hardware design error. Me personally, I suffered from that bug. The set was never repaired nor replaced and still rests in piece on a shelf in my house - as a recollection of a dishonest corporate behaviour.  Siemens never acknowledged the bug officially, just closed its mobile branch outright.