-cp and -clasaspath don't work for Groovy.bat in Vista

I have 2 files:
A.groovy :

package test
class A {
def test()

{ test1() }

def test1() {
}
}

B.groovy:

package test
class B extends A {
static void main(args)

{ new B().test() }

def test1()

{ super.test1() }

}

On Vista,

If I call "groovy -cp . B" I get:

error: no argument for:c
usage: groovy [options] [args]
options:
-p process files line by line and print result
(see also -n)
D,-define <name=value> define a system property
a,-autosplit <splitPattern> split lines using splitPattern (default '\s')

using implicit 'split' variable
c,-encoding <charset> specify the encoding of the files
d,-debug debug mode will print out full stack traces
-e <script> specify a command line script
h,-help usage information
-i <extension> modify files in place; create backup if
extension is given (e.g. '.bak')
-l <port> listen on a port and process inbound lines
-n process files line by line using implicit
'line' variable
v,-version display the Groovy and JVM versions

If I call "groovy -classpath B" I get:

Caught: java.lang.IllegalArgumentException: D:_projects\temp (D:_projects\temp
) is a directory not a Groovy source file.