Could you not get your JAR files to run just by double-clicking them, or does the error - "Setting maximum permanent space blah blah blah to blah" repeatedly pop up in the command prompt when you call it?

Unfortunately, I have fallen victim to the same problem while re-configuring the maximum
memory limit of Electric VLSI, a freeware EDA developed by Mr. Steven Rubin.
I've scoured forums and web pages in vain, then stumbled on a surprisingly simple answer below.

Kudos to Mr. Jacob Baker and Kuangming for providing a quick and effective solution.

On Wednesday, December 31, 2008 2:44:43 PM UTC, Jake wrote:
>  Kuangming,
> Try this,
> In Windows click Start, Run, then type in the command prompt "regedit" 
> (Registry Editor) and navigate to the path by expanding the appropriate 
> sections: 
> HKEY_CURRENT_USER / Software / JavaSoft / Prefs / com / sun / electric 
> Deleting folder electric folder will start you off like you are running 
> Electric for the first time (deleting this registry folder doesn't 
> affect the Electric jar binary or the Electric libraries, jelib files, 
> you've been working on but it will remove all of your key bindings for 
> example). 
> Note that you will loose all of your preferences (e.g., Key Bindings).
> Hope this helps, Jake.
> >>> KM < <javascript:>> 12/31/2008 5:12 AM >>>
> I recently downloaded and used the new Electric ver 8.08. I changed
> the memory allocation to 2048Megs and could not get Electric to
> restart. Everytime I restart Electric, I get this error message:
> "Current Java memory limit of 66MEG is too small, rerunning Electric
> with a memory limit of 1024MEG
> Setting maximum permanent space (2nd GC) to 2048MEG"
> Does anyone knows the solution to my problem?
> Thanks,
> Kuangming

I believe this solution works too with any other .jar program that had their max. memory limit erroneously configured. 

Aside from this, I've tried the following procedures too that didn't work for me. Maybe they could solve other unique problems for you:

>>Re-configuring the initial and maximum Java heap size.
In the command prompt, type "java -X" to get a full view of the possible command options.
Note: 64MB was the default setting for Electric.

Tried calling "java -d64 -Xms64m -jar electric-9.07.jar" but it didn't run.

Tried calling "java -d64 -Xmx64m -jar electric-9.07.jar" but it still didn't run.

Tried calling "java -d64 -Xms8374692574796789m -jar electric-9.07.jar" out of frustration. Waited in suspense if the program would run but it didn't. *sigh*

>>Linking the .jar extension to Java.
The caveman procedure to this is uninstalling and re-installing the latest version of Java.

>>Declaring the correct Java directory in your Path.
Go to "Advanced System Settings >> Environment Variables" and ensure that the correct directory is defined in the list of paths that appear.

>>Throw the computer out the window and make lots and lots of noise while dancing like a baboon. No, not because the problematic .jar file has driven you crazy, but because it is New Year's Day. 
Yep, Frohe Neues Jahr Alle Zusammen! :)