PGFPlots and hyperref don't seem to play well together for vertical text. For example, the ylabel (which is vertical) shows its hyperref box in the middle of nowhere instead of at the position and direction of the vertical label.
Does anybody know a workaround?
(Note two things: the hyperref box works well for rotatebox and for horizontal labels)
\documentclass{article}
\usepackage[]{hyperref}
\usepackage[]{pgfplots}
\begin{document}
\rotatebox{90}{\href{http://www.google.com}{hello}}bye
\newline
\begin{tikzpicture}
\begin{axis}[xlabel = {\href{http://www.google.com}{Time}}, ylabel = {\href{http://www.google.com}{Length}}]
\end{axis}
\end{tikzpicture}
\end{document}
EDIT: Although Jake's answer (and Martin's) does the job, the problem persists for "units" part of the label. (I should have posted the full problem in my question instead of a simplification). As in the picture and code below, see how it seem not trivial to rotate the units part and also make it appear the expected location (after the end of the word "Length"):
\documentclass{article}
\usepackage[]{hyperref}
\usepackage[]{pgfplots}
\usepackage[]{tikz}
\usepgfplotslibrary{units}
\begin{document}
A plot with units:\newline
\begin{tikzpicture}
\begin{axis}[y label style={rotate=-90}, x unit = {\href{http://www.google.com}{\mathrm{s}}}, y unit = {\href{http://www.google.com}{\mathrm{m}}}, xlabel = {Time}, ylabel = {\rotatebox{90}{Length}}, title = {Axis}]
\end{axis}
\end{tikzpicture}
\end{document}