QlikView didn't care about such special data-types - there are only numeric or string respectively the combination of both as dual-field. But this isn't a problem rather the opposite. You could solve it with converting/formating with functions like num(num#(Field, 'Format'), 'Format') your data within a : Preceding Load.
I had a similar problem with postal codes. Sometimes and apparently arbitrarily, QlikView loaded the values adding 0's to the left. For example, the value 7500 was sometimes loaded as 07500 and other times as 7500 in records from the same source having the value 7500.
After delving, the issue was related to nonprintable characters, and I solved it by removing all of them in the query, namely replacing CHAR(9), CHAR(13), CHAR(10) and CHAR(163) with the empty string '', as well as applying RTRIM and LTRIM functions to trim the result.