When I try and choose a few computers from my host list to compare in a graph I get the following error in my Safari browser on my mac AND on my Windows XP machine in IE7:

JpGraph Error
Cannot use auto scaling since it is impossible to determine a valid min/max of the Y-axis (only null values).

Months ago I had experienced this problem on my PC with IE7 but until recently it seemed resolved and now it's come back on both Safari and IE7. Do I have a local setting wrong or is this a back-end issue?

Fixed