[R] Rgui.exe - Error while tuning svm

[Andreas]

Hello,

if I try to tune my svm with the code:

Tune <- tune.svm(Data.Train, Class.Train, type="C-classification",
kernel="radial", gamma = 2^(-1:1), cost = 2^(2:4))

i get a windows Messagebox with a error in the application "Rgui.exe" and
the message: "Die Anweisung in 0x6c48174d verweist auf Speicher 0x00000000.
Der Vorgang "read" konnte nicht auf dem Speicher ausgeführt werden. ....."

is this a known error, or is there any mistake in my code?

regards Andreas