Extracting xticks from a plot handle

I would like to extract the vector of xticks values from a plot. I am using the GR backend.

For xlim I can do this:

h = plot(randn(10))
xlims(h) # returns a tuple with the two limits
xlims!(h, (-10,10)) # modifies xlims in the plot

I can modify the xticks using the same syntax:
xticks!(h,[-5,0,5]) # works

But I can not extract xticks from the handle:
xticks(h) # returns ERROR: UndefVarError: xticks not defined

Is this a bug, or am I missing some logic in this?