Chi squre distance and linkage function

Hi everyone. Following problem turned out. I need to compare and express similarity of set of histogram. Subsequently I need to cluster these histograms (linkage function). But the problem is, that have used Chi square distance so far. Chi2=sum((Hist(1)-Hist(2))^2)/Hist(1). The problem is, function linkage does not support this metric. Is there any way how to get rid of this difficulty?

thank every one!