The XXL survey is the largest survey carried out by XMM-Newton. Covering an area of 50deg$^2$, the survey contains $sim450$ galaxy clusters out to a redshift $sim$2 and to an X-ray flux limit of $sim5times10^{-15}erg,s^{-1}cm^{-2}$. This paper is part of the first release of XXL results focussed on the bright cluster sample. We investigate the scaling relation between weak-lensing mass and X-ray temperature for the brightest clusters in XXL. The scaling relation is used to estimate the mass of all 100 clusters in XXL-100-GC. Based on a subsample of 38 objects that lie within the intersection of the northern XXL field and the publicly available CFHTLenS catalog, we derive the $M_{WL}$ of each system with careful considerations of the systematics. The clusters lie at $0.1<z<0.6$ and span a range of $ Tsimeq1-5keV$. We combine our sample with 58 clusters from the literature, increasing the range out to 10keV. To date, this is the largest sample of clusters with $M_{WL}$ measurements that has been used to study the mass-temperature relation. The fit ($Mpropto T^b$) to the XXL clusters returns a slope $b=1.78^{+0.37}_{-0.32}$ and intrinsic scatter $sigma_{ln M|T}simeq0.53$; the scatter is dominated by disturbed clusters. The fit to the combined sample of 96 clusters is in tension with self-similarity, $b=1.67pm0.12$ and $sigma_{ln M|T}simeq0.41$. Overall our results demonstrate the feasibility of ground-based weak-lensing scaling relation studies down to cool systems of $sim1keV$ temperature and highlight that the current data and samples are a limit to our statistical precision. As such we are unable to determine whether the validity of hydrostatic equilibrium is a function of halo mass. An enlarged sample of cool systems, deeper weak-lensing data, and robust modelling of the selection function will help to explore these issues further.
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