command line function failing?

Hi all need some advice with a command line problem i seem to be having...

the code i have is as follows

Code:

wget=[[NSTask alloc] init];
	[wget launchPath:@"~/share/emacs/pkg/osx/"];
	[wget setArguments:[NSArray arrayWithObjects:@"osascript -e 'mount volume """"smb://workgroup; : @homepc/x drive""'",nil]];
	[wget launch];
	[wget release];
	wget=nil;

this compiles fine but when i run it and click my button i get the following error from the xcode console..

2008-01-13 22:00:33.137 HelloWorld[2310] *** -[NSConcreteTask launchPath:]: selector not recognized [self = 0x37b730]

i get the feeling this is obviously something todo with my launch path but i cannot seem to fine OSASCRIPT when i spotlight it, so i am at a bit of a loss i have also tried google but nothing seems to indicate where it is.

any ideas anyone?