ShortFormIDs can't begin with number in 1.5.1 - but worked fine in 1.4.3

[dosumis]

In 1.4.3:

test = Brain()
test.addClass("5ca4b0f0-23b3-11e4-b0bd-a8206614dd49")
<brain#5ca4b0f0-23b3-11e4-b0bd-a8206614dd49>
test.knowsClass("5ca4b0f0-23b3-11e4-b0bd-a8206614dd49")
True
test.getSubClasses("Thing", 0)
[5ca4b0f0-23b3-11e4-b0bd-a8206614dd49]

But in 1.5.1:

test = Brain()
test.addClass("5ca4b0f0-23b3-11e4-b0bd-a8206614dd49")
<brain#5ca4b0f0-23b3-11e4-b0bd-a8206614dd49>
test.knowsClass("5ca4b0f0-23b3-11e4-b0bd-a8206614dd49")
False
test.getSubClasses("Thing", 0)
[ca4b0f0-23b3-11e4-b0bd-a8206614dd49]

Note the missing first digit. Only digits seems to be affected. All leading digits are removed during class generation. No errors are thrown. The same issue is seen when loading from a file.

[loopasam]

ok weird... might be an OWL-API problem, thanks for providing the test-case, I investigate.