Steps to reproduce:
1. Start with fresh instal of Fedora Core 6
2. Start GnuCash (command line to see the error, but it crashes either way)
3. Select Import QIF files
4. Provide a file with invenstment account transactions - I did have buy, buyX, intinc, sell, sellx in my file (may be reinvested div as well)


Stack trace:
 192: 11   (case action-symbol ((buy kauf) (quote buy)) ...)

/usr/share/gnucash/scm/qif-import/qif-parse.scm:192:9: In procedure memoization in expression (case action-symbol (# #) ...):
/usr/share/gnucash/scm/qif-import/qif-parse.scm:192:9: In file "/usr/share/gnucash/scm/qif-import/qif-parse.scm", line 191: Duplicate case label aktzu in expression (case action-symbol ((buy kauf) (quote buy)) ((buyx kaufx) (quote buyx)) ((cglong kapgew) (quote cglong)) ((cglongx kapgewx) (quote cglongx)) ((cgmid) (quote cgmid)) ((cgmidx) (quote cgmidx)) ((cgshort k.gewsp) (quote cgshort)) ((cgshortx k.gewspx) (quote cgshortx)) ...).

Other information:
aktzu is at both lines 222 and line 260  of /usr/share/gnucash/scm/qif-import/qif-parse.scm

I removed it from line 222 and everything worked. Since my file was in english I did not need this in any of the 2 places - you need to verify which one is the correct place for this key.