If the tablespace is not hardcoded in the dmp file create table statements then you should be able to import without a problem. So my suggestion would be to first try something like the following (for more details: http://docs.oracle.com/cd/E11882_01/server.112/e10701/original_import.htm)
imp user/password@instance file=FILE.dmp log=LOG.log fromuser=DMPSCHEMA touser=NEWSCHEMA
If you get IMP-00017 errors. Then you have to take the longer route. You need to first create the tables and then import with ignore=y.
To first create the tables you need the DDL statements, which you can obtain by running:
imp user/password@instance file=FILE.dmp log=LOG.log full=y indexfile=INDEXFILE.log
The INDEXFILE.log will contain all the create table statements. Find and replace "spaceA" with "spaceB", create the tables, and then run the import with the ignore=y parameter which will ignore table creation errors (since tables already exist) and load data:
imp user/password@instance file=FILE.dmp log=LOG.log fromuser=DMPSCHEMA touser=NEWSCHEMA ignore=y