Webstart cache path error for Java >= 7u65

FULL PRODUCT VERSION :
java version "1.8.0_11"
Java(TM) SE Runtime Environment (build 1.8.0_11-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.11-b03, mixed mode)



ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

EXTRA RELEVANT SYSTEM CONFIGURATION :
Current system locale is "Serbian (Latin, Serbia)" set inside:
Control Panel -> Regional and Language Options -> Administrative (Advanced) -> Language for non-Unicode programs

A DESCRIPTION OF THE PROBLEM :
From account that has Unicode letters in its name is impossible to start any JNLP.
System locale is set correctly, but path to temporary java files is wrongly interpreted. This problem started with java version 7u65.

For Java versions before 7u65, JNLPs are starting as normal if correct system locale is set.

REGRESSION. Last worked in version 7u51

ADDITIONAL REGRESSION INFORMATION:
java version "1.7.0_51"
Java(TM) SE Runtime Environment (build 1.7.0_51-b13)
Java HotSpot(TM) 64-Bit Server VM (build 24.51-b03, mixed mode)


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Log in on administrator account
2. Chose Serbian language from the Language bar
3. Create user spetrović (with last letter in Unicode)
4. Set "Current language for non-Unicode programs" to Serbian (Latin, Serbia) inside:
Control Panel -> Regional and Language Options -> Administrative (Advanced) -> Language for non-Unicode programs
5. Log in on spetrović account
6. Try to launch JNLP

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Normal launch of JNLP
ACTUAL -
Error in starting JNLP file. Dialog is shown with error:
Could not load file/URL specified: C:\Users\spetrović\AppData\LocalLow\Sun\Java\Deployment\cache\6.0\10\6b804dca-13d2a078


ERROR MESSAGES/STACK TRACES THAT OCCUR :
CouldNotLoadArgumentException[ Could not load file/URL specified: C:\Users\spetrović\AppData\LocalLow\Sun\Java\Deployment\cache\6.0\10\6b804dca-13d2a078]
at com.sun.javaws.Main.launchApp(Unknown Source)
at com.sun.javaws.Main.continueInSecureThread(Unknown Source)
at com.sun.javaws.Main.access$000(Unknown Source)
at com.sun.javaws.Main$1.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

REPRODUCIBILITY :
This bug can be reproduced always.