diff --git a/src/lib/commands/fina.c b/src/lib/commands/fina.c
index b80cce07..c2280a22 100644
--- a/src/lib/commands/fina.c
+++ b/src/lib/commands/fina.c
@@ -81,6 +81,10 @@ fina(void)
 	    xdur += rdur;
 	    rdur = 0;
 	}
+	if (xdur < 0) {
+	    rdur += xdur;
+	    xdur = 0;
+	}
 
 	if (CANT_HAPPEN(loan.l_ldur == 0))
 	    continue;
diff --git a/src/lib/commands/repa.c b/src/lib/commands/repa.c
index c22a96b1..b2f2e0ae 100644
--- a/src/lib/commands/repa.c
+++ b/src/lib/commands/repa.c
@@ -84,6 +84,10 @@ repa(void)
 	doubletime += normaltime;
 	normaltime = 0;
     }
+    if (doubletime < 0) {
+	normaltime += doubletime;
+	doubletime = 0;
+    }
 
     rate_per_sec = loan.l_irate /
 	((double)loan.l_ldur * SECS_PER_DAY * 100.0);
diff --git a/src/lib/subs/disloan.c b/src/lib/subs/disloan.c
index 625de08c..bf7db5f3 100644
--- a/src/lib/subs/disloan.c
+++ b/src/lib/subs/disloan.c
@@ -94,6 +94,10 @@ disloan(int n, register struct lonstr *loan)
 	doubletime += normaltime;
 	normaltime = 0;
     }
+    if (doubletime < 0) {
+	normaltime += doubletime;
+	doubletime = 0;
+    }
 
     rate = ((double)loan->l_irate / 100.0) / (loan->l_ldur * SECS_PER_DAY);
     owe = ((double)loan->l_amtdue *