Cant create a database in a specific folder in ios - iphone

Question

I am working on a jailbroken device and I am not developing for the app store.
I create a database in my code in the beginning using this code.
if(temporaryvariable == 0 ) {
if (![[NSFileManager defaultManager]fileExistsAtPath:#"/Library/Myapp/Storage"]) {
NSLog(#"Creating Direcotory Documents");
[[NSFileManager defaultManager] createDirectoryAtPath:#"/Library/Myapp/Storage" withIntermediateDirectories:YES attributes:nil error:nil];
}
storeURL = [NSURL fileURLWithPath:#"/Library/Myapp/Storage/my.sqlite" isDirectory:NO];
} else {
storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:#"my.sqlite"];
}
The code works fine if I change the db path to root/var/mobile/documents. But when I use the path given in the above code the app crashes with the following error.
Unresolved error Error Domain=NSCocoaErrorDomain Code=256 "The
operation couldn’t be completed. (Cocoa error 256.)" UserInfo=0x334a30
{NSUnderlyingException=authorization denied, NSSQLiteErrorDomain=23}
,,, {
NSSQLiteErrorDomain = 23;
NSUnderlyingException = "authorization denied"; } with store url file://localhost/Library/Myapp/Storage/my.sqlite
Abort trap: 6
I even tried changing the permissions of the storage folder but it doesn't work. Help me with this error please
EDIT:
This folder is actually the main bundle of my application on the jailbroken iphone.