Problem with Delt() from quantmod

Dear All,

I'm having a problem with using Delt() on a xts object with a vector of
k values. With a single k value I have no problems and with vector of
values instead of a xts object I'm also able to get what I want. Let's
see illustrative examples:

x

? ? ? ? ?GSPC.Adjusted
2009-04-01 ? ? ? ?811.08
2009-04-02 ? ? ? ?834.38
2009-04-03 ? ? ? ?842.50
2009-04-06 ? ? ? ?835.48
2009-04-07 ? ? ? ?815.55
2009-04-08 ? ? ? ?825.16
...

class(x)

[1] "xts" "zoo"

Delt(x)

? ? ? ? ?Delt.1.arithmetic
2009-04-01 ? ? ? ? ? ? ? ?NA
2009-04-02 ? ? ? 0.028727129
2009-04-03 ? ? ? 0.009731777
2009-04-06 ? ? ?-0.008332344
...

Delt(x,k=1:3)

Error in attributes(.Data) <- c(attributes(.Data), attrib) :
?length of 'dimnames' [1] not equal to array extent

Any help is most welcome.

Thanks,
Luis

--
Luis Torgo
?FC/LIAAD - INESC Porto, LA ? ?Phone : (+351) 22 339 20 93
?University of Porto ? ? ? ? ? Fax ? : (+351) 22 339 20 99
?R. de Ceuta, 118, 6o ? ? ? ? ?email : ltorgo at liaad.up.pt
?4050-190 PORTO - PORTUGAL ? ? WWW ? : http://www.liaad.up.pt/~ltorgo