Code:
import dateutil.parser
from datetime import datetime

a='0001-01-01T00:00:00+02:00'
b='1964-01-01T00:00:00+02:00'
ia=dateutil.parser.parse(a)
ib=dateutil.parser.parse(b)
print a
print ia
print b
print ib

output:
0001-01-01T00:00:00+02:00
2001-01-01 00:00:00+02:00
1964-01-01T00:00:00+02:00
1964-01-01 00:00:00+02:00

On wiki ISO 8601, under Combined date and time representations:
If a time zone designator is required, it follows the combined date and time. For example "2007-04-05T14:30Z" or "2007-04-05T12:30-02:00"

I know you may have to fall back template on date such as 1/1/1, but this is ISO and according to my reading, it does not require one.

BTW, my input comes from public posted information.

Thanks,

Perhaps I'm misinterpreting your message, but this doesn't seem like a problem with datetime module. The issue is with dateutil module, which is not the part of the standard library and is not developed here. Also, I can reproduce this issue on 3.4 (though I doubt it's awfully relevant).